Paul,
Well - I bought a line-1 and compared it with my Statement D1 - and it sounded no better, and IMHO a little worse. It was definitely harsher on the top end. To be honest, I don't know if it was the line-1, the modded JD100 I swapped in at the same time, or both together. I definitely was not happy though; it sounded more solid state than my SS gear did!
The real clincher was badly recorded CD's; I don't know if it is the D1's upsampling, but with most of my rock CD's it was downright painful to listen on the line-1. The D1 seemed to take that edge off of it.
I then bought a line-2 in mint condition; and haven't even taken it out of the box yet. ;-) I think I'm just going to sell it, sell the wally-modded JD100, buy another stock JD100 and stay happy with my D1 for now and enjoy my music.
My only complaint on the line series is that the HT bypass loop is only single ended, not balanced. Other than that, it's an incredibly beefy and well built piece of equipment.
As far as damage, none whatsoever; it worked perfectly. I something could happen, but it was fine for me.