well flatting is more likely the better option with these stack sizes, raising with the 20bb stacks is a bad idea, what would your plan be when you get 4 bet? (which is highly likely with so much action already) I dont think we can call anything, and there is very little chance of our 3bet getting folds from everyone. Even if somehow the 3bet makes the flop, the stack to pot ratios won't allow you to see turns and rivers easily with flush draws, and I don't think you would be confident in getting it in with an ace.

would like to hear peoples opinions on flatting, I feel its too risky, as even with a good draw on the flop it will still be tough to contunue alot of the time.

Imo fold > flat > raise

i am thinking with 40 bbs you have to find spots to try to get some flops in with favourite pot odds.

if you do flat here, and you do hit a great flop 66,, ace  6, flush draw, or opened straight draw iwth 534 . you stand to win a big pot should there be passive on such flops.