I don't know about anyone else but i found this difficult to follow, so im going to repost the hand and action if you don't mind.
Live cash game £.25/.5 NLHE
Stacks (approx)
UTG+1 £200
CO £70
SB £50
BB (Hero) £200
Hero is dealt

Preflop: UTG+1 Raises to £2, CO Raises to £10, SB Calls £10, BB Calls £10, UTG +1 Calls £10
Flop (Pot = £40):

Action: SB is all in for £40, Hero?

I think we have to fold here with two people to act behind us and the fact that we are probably not far ahead of sb's range if at all. Preflop is kind of marginal given the stacks, i don't hate folding here if we read the co to be solidish.