The little jobsite table saws can have plenty of
power for basic scenery construction. Downsides include the obvious size issue- you don't have much table to work with, so long rips or sheets require help, or you
build out from your saw until you have a cabinet saw sized table and outfeed, but your space is limited... Also, the direct drive motors with no enclosure are very loud compared to a cabinet saw, and a fair amount louder than any circ saw I've laid ears on.
Things to watch for in my experience have to do with the fact that most of what you're paying for in the job site saws is a big-ass motor that spins a blade, and the finer points like a fence and guard that work and any other accessories may get less attention than they should. That said, all the usual decent brands I've used have been okay (which are Bosch,
Makita and DeWalt) and the DeWalt I have at home now has a really impressively good fence and guard/
riving knife. When I was researching that
purchase the DeWalts seemed to be a near universal favorite as far as that goes. Bosch and
Makita seem good too. I am very pleased with my DeWalt for about $350 on sale.
If in your space situation and on a tight budget (if more money, sure, look at a larger
portable TS,
panel saw,
track saw setup) I wouldn't hesitate to get a sub-$400 DeWalt jobsite saw for ripping boards, plus a
track saw or plain circ saw with shop built guides for sheet
goods. Longevity of that setup? I don't know, but I bet a decent brand gets you your money's worth even if it is dead in 3 years instead of 30. My Sawstop cabinet saw was around $3K with some options and dust collection. It'll last a very long time, can do more, and is more fun to use, but that's near ten times the cost of my jobsite saw that is totally usable in every reasonable way if a larger saw isn't an option. Oh, and my $100 Rigid vac does a pretty solid job on the DeWalt saw's dust port, too.