As commonly played, Stayman requires at least game-invitational values. But sometimes your hand strength depends greatly on whether you have that 4-4 major fit.
Consider this holding when partner opens a 15-17 notrump:
♠ 10
♥ Q762
♦ A1096
♣ J764
If the contract is notrumps you have 7 points. If it's hearts you have 10 points. What would you do?
At IMPs you don't want to miss games. I would bid 2♣ and then 4♥ if partner shows hearts, otherwise 2NT. You might go down in 2NT or 3NT, but sometimes 3NT will make.
At matchpoints you risk going down in 2NT, but +90 is seldom a great result. 3NT will be top or bottom. Finding a heart fit will be excellent even if you don't force to game. Again I would try 2♣.