Here's a heads-up to the Broadway nay-sayers, the doom and gloomers and those who want to tear down the new Spider-Man musical just because they think they can – start eating your words, people.

Spider-Man: Turn Off the Dark is so spectacular and so awe-inspiring that all the haters – and there seem to be plenty of them out there – look like complete morons.

To those who have declared the most talked about show ever to arrive on Broadway to be dead on arrival, a ridiculously expensive ($65 million) folly that never had a snowball’s chance in hell of succeeding . . . well, we’ve had an awful lot of snow in New York this year, and Spider-Man is so sizzingly hot that it won’t have any problem melting away all of the bad press that’s greeted its arrival on the Great White Way.

For sure the production, with music and lyrics by Bono and The Edge of U2 and story and direction by The Lion King’s creative genius Julie Taymor, has had its fair share of problems, led by the injuries suffered by some of its cast members, including a horrifying fall by one of the stunt doubles playing Spider-Man.

Technical glitches have plagued some of the preview performances, and the official opening date has been pushed back several times – it was to bow in December, but now the new date is March 15 – leaving critics howling that the preview window has stretched way beyond the Broadway norm, and others proclaiming that all the difficulties only prove that Spidey’s web has been a tangled mess from the start.

We went to the Saturday afternoon matinee at the show’s Foxwoods Theater home on 42nd Street.  There wasn’t an empty seat in the house – the previews are the hottest ticket on Broadway, which of course is a good thing for the producers who hope to eventually recoup their initial record-setting investment.

The performance on Saturday was technically flawless.  Actually, it was a technical sensation completely unlike anything ever staged on Broadway or anywhere else, a feast for the eyes that’s so dazzling, so “wow, wow, wow” that you’ll be left totally awestruck.

Spidey flies and swings through the theater, he leaps from balcony to balcony, he stages a battle with his arch-enemy the Green Goblin right over the heads of those in the lower orchestra seats, he climbs all over the elaborate sets . . . it’s just a wonder to watch, and an unbelievable achievement to actually execute.

Taymor brought the brilliance of her inventive mind to Broadway with The Lion King, which is still going strong 14 years on, but she’s utterly raised the bar to a soaring height – which is exactly what she, Bono and The Edge said they wanted to do – with Spider-Man.

The show’s storyline has also gotten battered around by some early commentators – it’s not cohesive, it’s hard to follow, there is no narrative, blah, blah, blah.

As any fan of the Spider-Man comics or movies will know, the story in a nutshell centers around Peter Parker and his girl Mary Jane. Peter transforms into Spidey and saves the world from evil but still tries hard to maintain his identity as Peter when he’s not weaving his webs.

The story in the Broadway incarnation stays true to this line, and there’s nothing at all wrong with the Taymor and Bono/Edge new interpretation.  The cast members are excellent, so talented and so obviously full of enthusiasm for what they’re doing.

Spider-Man isn’t Shakespeare, and anyone looking for high drama with a deep and profound meaning is fortunate because there are lots of those type of shows playing on Broadway and elsewhere in the city.

Taymor has added the new character of Arachne, a sinister female spider for Spidey to contend with.   The character proves to be an integral part of the story – maybe a bit too much in the second half, which Taymor acknowledges is still being worked on in advance of the opening in March.

If there’s one legitimate complaint that’s been voiced about the show, it’s that the ending lacks a final jolt of oomph given all the razzle dazzle that preceded.  If I was Taymor, Bono and The Edge I’d definitely shake up the final 15 minutes some more, and let Spidey go out with a wondrous leap that will send audience members rushing back to the box office for more tickets even faster than they already undoubtedly will.

So what of Bono and The Edge’s musical score?  As one half of U2, the world’s most important and celebrated rock band for the past three decades, they certainly have huge reputations to live up to . . . and they’ve done exactly that, with great aplomb.

Their score is an artistic triumph that they can and should be extremely proud of.  It’s edge-y (excuse the pun), it’s vital to Taymor’s narrative and the overall feel of the show, suspenseful when it needs to be, mellow when it needs to be.

And it’s absolutely tinged with U2-isms . . . Edge’s distinctive guitar hooks, Bono’s vintage prose and knack for telling a story.  One of the band’s most popular hits, “Vertigo,” even makes a fun appearance in a disco scene with Peter and Mary Jane.

As with seemingly everything Spider-Man related, the music has also come in for a wallop in some quarters.  One critic from Bloomberg sniffed, “As with most rock stars, Bono and The Edge haven’t a clue about writing for the theater.”

Oh, please.  As if the “theee-aah-tuh” is so above everything else – like, selling more than 150 million albums, touring the world with sell-out stadium shows, and creating unforgettable songs that will stand the test of time for years and years to come.

That’s what Bono and The Edge have already accomplished.  They don’t need Broadway … but Broadway, with slumping ticket sales, sure could use some of their magic.

To be part of a band like U2 is a career achievement that the rest of us can only dream of, and their score for Spider-Man is yet another notch on a belt full of successes.

The bottom line from our vantage point?  If you want to be entertained on Broadway like never before, Spider-Man: Turn Off the Dark is just the ticket.  Fans at the performance we saw – especially the many children – were enthralled by what they witnessed, with lots of “oohs” and “aahs,” wide eyes and open jaws.   It’s people such as these who will determine whether the show stands or falls, and from what we can tell, they’re very much ready to stand with Spidey.

There will be professional critics who undoubtedly won’t be fans when the official reviews come out after March 15 – but these people also don’t like apple pie or cute babies.

Okay, just kidding on that last point -- of course, everyone is entitled to an opinion -- but if ever a show has the power to be critic-proof, Spider-Man is it.  But hopefully it won’t need to be, and hopefully the professional reviewers who eventually put pen to paper will look at the show with open eyes, and forget about its past controversies.

The Marvel Comic creation is a marvel in every way – and those who want to see it fail will be sorely disappointed because it won’t.

U2's 'Spiderman'