Me too. About 3 weeks ago.
As has been said, I'm not sure how much difference it made with distortion, because I only have this one guitar I can't do an A/B comparison, but I think it did wonders for the clean tone. 'Bell-like', as mentioned by a previous poster.
I thought it would add tons of sustain, but I don't think it really did... it may have increased sustain from 12 seconds to 14 or 15 seconds? Maybe. But during those same 12 seconds of sustain I think the sound is fuller longer.
My piece of crap '97 mexi strat has a poplar body that weighs less than 3 lbs and is made of 5 to 7 pieces- so that is why this guitar still doesn't sound amazing yet.
I would definitely buy the trem block.
I really like that the trem arm doesn't flop around, but stays in position because they make the threads so that the arm screws into the block pretty tight. Very nice!