Same ol' answer, really: depends on what you want.
How loud do you want it to be? How easy to carry? How close to the original modelled amps do you want it to sound?
With a head you'll need a seperate cabinet like a 4x12 or a 2x12, etc. More speakers = more surface area = more air being moved = more volume. A combo is generally easier to carry than a half stack and, IMHO, sounds "smaller". You need to weigh the pro's and con's against what you'll be doing.
Personally - and that's just me - I went for the head and 4x12 cabinet. I just wanna be the loudest mofo on stage! He he he. Line6 suggests you use their cabinets because you'll get a closer representation to the actual amps they're modelling. I didn't go that rout but it might be true. You'll have to do your own listening and decide. I went with the heaviest cab I could find for the money. I bought an early 90's Jackson cab off e(vil)Bay. It weighs in at a comfy 110lbs.
and won't rattle even in an earthquake (I had that problem with a Marshall 1960a 4x12 cab once). My gain sound is basically a warmed up version of that classic Metalli-chunk tone so there's lots of bottom end to shake the cab with. Your sound may not do this so it may not be a consideration for you.
I believe both the Flextone and the Vetta combos are open backed combos. Opened back combos and closed back combos sound slightly different from each other and, again IMHO, a lot different then a 4x12. Once more, it depends on what kind of tone you're going for.
Suggestion: stop asking for suggestions
and go to that store you were talking about earlier. I know it's a few hours away (you said as much) so make sure you're able to have a few hours to test your a$$ off. Time to get your feet wet, so to speek. Test some combos and half/full stacks and see for yourself what difference it makes and what will best suit what you're looking for. Call ahead to see if they have Line6 equipment and/or the Deville (read: any of the other equipment already talked about in this thread). If not, find a store that does and bring your favorite guitar with you. Ear plugs are optional ... he he he
Have fun!
LJ
