I'm upgrading to a new head. I've used both the SVT- 4PRO and the mesa 400+ but i don't know which one to go with. I also was curious if anyone knew which one was better for working in the studio (right now I'm using an older ampeg 4 x 10 cab at 8 ohms). The ampeg svt 2 also seems like a good head, but I haven't had a chance to play one yet. All of these amps are fairly expensive, so I'm open to any opinions and/or suggestions. Thanks!