So, I'm considering a new head. The cab I use is a three-way Dr. Bass 15/8/horn cab rated for 600 watts and 8 ohms. I have a hookup for either a Hartke LH1000 or GB shuttle 6 at very, very good prices. I won't have a chance to play through either before I buy. I play a P-bass with flats into this rig. I'm looking for a clean, warm tubey sound, and like tons of headroom, but am a bit nervous about the hartke putting out 700 watts at 8 ohms into a cab rated for 600. Which of these two amps would you go for and why?