Here we go: I'm using a Mesa 400+ with the Preamp valve replaced as recommended here in other posts but there's something with the mids on this amp that I'm not completely happy about...not sure how to explain it but it has been mentioned before in other threads. I'm seriously thinking of selling it and I have a good chance to get an SVT 4 Pro, SVT 5 Pro or a DB751 for really good prices...Different amps, I know, Mesa all valve head and the other ones not but, in your experience what would you recommend? I have to say I like to have a bit of dirt in my sound, not much but have that break up in my tone. I run my amp through a Bergantino NV610 and I now mainly use a Fernades Deluxe Gravity 5 strings and sometimes a Sadowsky UV70 or Fender Geddy. Thanks in advance for all your advice.