I am closing in on my rig, have the $$$ in hand, and would like you knowledgeable tone gurus to help me make a decision here. Obviously the EA and Thunderfunk are highly regarded around here, and I would probably be happy for a long time with either one. Both would be a good choice for a lightweight all in one head to drive a 4 ohm load to very high volume. But which one wins out, and why? In the third corner, there is the pre/power amp choice. It wouldn't be as lightweight as the other two, and wouldn't be as plug-n-play friendly, but would be more versatile. If I go this route, I would probably put together a rack with 800-1000 watts, a Sansamp RBI, and some kind of clean, modern sounding preamp. BBE, Alembic, Demeter, etc. As far as the iAmp 800 vs. TFB420, I would like for people who have experience with both of these heads to answer a few questions for me. 1. How do each of them sound for loud rock, slap, and R&B? 2. How would you characterize the tone of these amps, in your own words? 3. How honest, in your opinion, is the power rating? If I should consider a rack system over these heads, explain why, besides the versatility angle. Thanks for all of your help!!!