I've whittled my choices of amps down to the Hartke 3500 or the 4000. They are both in my price range (less than $500 new) and have the watts I want at 4 ohms (300-500). I like the simplicity of the 4000. It's gotten alot of great reviews and only one negative one, whereas the 3500 seems to either be good or bad...seems you get a great one or a lemon...which leads me back to the 4000. 400 watts into a 4 ohm cab (mine is a 4 ohm 410). It has a wide ranging parametric EQ with a Sub-bass control feature for five string basses. It has a tuner by-pass switch and a sub-woofer output for extreme lows if one wanted to go that route. It looks very intriguing. Has anyone had any experience with the Hartke 4000 bass amp? I would appreciate any feedback on these amps...good and bad. Thanks.