I have a Mesa Dual Rec. Solo head, and I'm pretty sure I need new power amp tubes, and maybe new pre, but if not I'd still like to change them regardless. As of now just stock Mesa tubes are in it, and I was considering Sovtek KT66 and 12AX7LPS and whatever Sovtek 5U4Gs where of a not-as-expensive price.

If anyone wants to recommend me anything for a really clear, heavy, gainy tone; then lead me in the right way.

well for one the Dual Recto has a fixed bias. so that narrows down your choice in tubes dramatically. and the Dual Recto isnt an amp to throw in the "cheapest tubes you can find".

i suggest taking it to a good tube amp tech. and tell him what kind of sound you want. that would be the safest way, for both your amp and your sound.

[edit] the fall of troy > everything.
I went to the guy at eurotubes and ordered a "custom setup" or something like that. It sounds reallt cool but the JJ's are alot different from Mesa tubes. I switched the bias to EL34's and I turn up the power amp more than I used to but it sounds really good. Nice price too. I don't really like the guy at eurotubes because I think he is really biased but he gave me a good setup and I think I would get it again. But Sovtek's are real good and its up to you.