No upgraded tubes. I thought about picking them up because I heard they would brighten things up a bit, but after hearing the amp, even with my LCD, I did not want anything brightened up. At first I was worried because of how dark everyone said the LCD was, but the top end is just fine in my non-professional opinion. All my gear is stock except the D1 which has upgraded OpAmps.
I'm most excited to hear the TH-900 as they were next on my list of must-haves. I came close to pulling the trigger several times but got scared off since I've never actually heard them. I keep hearing that they sound like a better version of the D7000 which I also never heard but then I heard that the D7000 sounds like a big brother to the newer D600 (some of the worst headphones I've heard and the only pair I've ever returned.) I'd also like to hear so nicer DACs and some LCD-XC if a pair shows up. STAX are on my radar too of course and some Audio GD gear since I'm looking to sneak one onto my wife's desk at some point. I'm also considering putting a tiny Schiit Stack on my kids' desks since they primarily use my Q701 and X1.
I'm hoping a few of you will be pleasantly surprised by my HP100s also. I think if more people hear these cans they'll get a great reputation. For $150-200 they sound great.
I may like to purchase a replacement amp some day, this meet may help in that decision. 
