I still run my 20 year old amps, and try to as much as often.Really enjoy my old Autotek White Mean Machines(approx 15 left),and BTS Bass Thrust Series(approx 12 left) the most..Have a few HiFonic VII, and VIII series left(approx 8 or ten)..a coupe of USA US Acoustics Series II 2150s( a pair out of about 20-35 on a collection) 1- USX 800-F left..I have two of those Cross Fire TEK 100.2 left, twoPPI Version Special Editions A2050 and A2075,2-P2050,and P2075,1 JBL GTQ 400 left out of 6,1-JBL GTS 600 left out of 2,1 MTX Blue Thunder Pro 75.2 left( had a massive collection of those at one time),Clarion 50x2,One Audio Gods 75x2 left,Alpine 3525(2 left out of 4) ,3522(4 left out of 8), 3527(1 left out of 2)2-3523s left, 1- 3540 left out of 4..I think I still have 1-3513s out of a pair..2- Concord 20.2 left, had 4-50.2s,1-Audiobahn HCT 4125 left out of 3..1-Mmats D300HC white and Mint,1-S. Stream USA 204 left out of 3,1- S.Stream SA-80 left.( had a pretty massive collection of 300s,500, 60s,ect).My oldest and still clean as hell and my first Autotek is an A-182 and still woks great.Not to mention some older x-overs, and Eqs.and subs and speakers.I still run the hell out of whatever I have when I get tired of running certain amps.I still have quite a few newer amps also, but seem to go back to the older ones for some reason.Ive always said.. run what you have..or what you can afford..as you can always uprade later.