Are NHT VT2.4's harsh, or is it just me?

Your ears are indeed accomodating throughout a listening session, ESPECIALLY if you listen at high SPLs. I was at Boston's Symphony Hall last Wenesday for an open rehearsal of the BSO with guest Andre Previn conducting the Ravel Left-Hand Piano Concerto with Thibodeau (sp); I was in 6th row center, and the opening orchestral minutes were breathtakingly beautiful and LOUD. Then the 9' Steinway entered with a thin, wimpy sound! Sounded like a fortepiano!
I then remembered that I was sitting slightly BELOW the
soundboard, and well below the lid's projection, and that the front orchestra seats are simply not kind to pianos at SH. Yet within about 10 minutes everything was fine. Did the piano change? Of course not. Did Thibodeau get MORE dynamic? Nope. Just pychoacoustic accomodation.........
Your NHTs WILL continue to fill out their bottoms with time, but I suggest you either be patient, and NOT force it by ruining your ears in the meantime, and perhaps follow a prescribed artificial break-in as described above.
I'll bet that when you listen tonight you'll be disappointed with the first two minutes of music because the sound IS still thin and too analytic. You need to give the woofers' spiders and surrounds time...not blast your ears into submission! Take it easy....

Thank you for the advice. I plan to give them time and I definitely will not harm my ears. I can't listen too loud with everyone asleep! (Can't wait to finish dedicated music/home theater room in the basement).

I sounds as if you think these speakers may be satisfying after some substantial break in?

P.S. You asked about the switch. The switch on this speaker is to activate rear midrange and tweeter for a bipole effect on movie soundtracks. I flip the switch off for music listening.

They're harsh.

Have you had the opportunity to listen to them?

According to NHT's website, the 2.4 has the same 1" aluminum dome tweeter as the venerable 3.3 and the favorably reviewed (by SGHT) VT 3 system. They SHOULD sound good after break in.