A head and cabinet is your best bet.
Combos are nice but don’t have the projection by them selves to hang with the Twin.
Any good ss 300 + watt head and either a 4x10 or 2x12 cab will be good for starters.
Avatar cabinets have been getting rave reviews for sound, quality and price.
The limiter here is your budget.
So unless you find a great Craig’s list deal we’ll forget about tubes for now.
GK Backline amps work well, are fairly inexpensive, have been around forever and seem to hold up.
The Mark bass amps got rave reviews early, but that may have been ‘the new toy syndrome’ they’re worth checking out though
I’d like to check this out.
http://bass-guitars.musiciansfriend.com ... e-Bass-AmpAs always, look at used gear first.
MM