I'm finding myself in marginal spots in big multiway pots like this, and I am looking for the way to squeeze the most out of them. SB is a solid player, UTG+2 is a calling station donor type. Thoughts on all streets, but particularly river - is this a bet or a check behind?

PokerStars 10/20 Omaha/8 (10 handed) from (Format: Bet The Pot)

Preflop: Hero is MP1 with , , , .
2 folds, UTG+2 calls, Hero calls, 4 folds, SB raises, 1 fold, UTG+2 calls, Hero calls.

Flop: (7 SB) , , (3 players)
SB bets, UTG+2 calls, Hero raises, SB 3-bets, UTG+2 calls, Hero caps, SB calls, UTG+2 calls.

Turn: (9.50 BB) (3 players)
SB bets, UTG+2 calls, Hero calls.

River: (12.50 BB) (3 players)
SB checks, UTG+2 checks, Hero bets, SB calls, UTG+2 calls.

Final Pot: 15.50 BB

I think you really need to raise that turn; that seems to be a huge card for you. Going to a cap on the flop and only calling the turn when your hand improves hugely seems counter-intuitive.

I think the river bet is very thin; at first I liked it, now I can't quite make up my mind . I think it's pretty marginal either way so I wouldn't lose sleep over it. I often like to put in a bet in situations like this because I think your showdown equity is probably close to 1/3, and there's just a chance you'll push out someone with a better low (I think any better high is calling) to grab a sneaky half when you'd be getting nothing for checking down.