I prefer checking behind the turn. There are no longer any cards you are concerned about falling now that you have top pair. You can actually be value towning yourself when you bet here, and you are quite unlikely to get paid off on the river if you do hit your spade even if you are lucky enough to get a call on turn from villain when he's behind.

You almost guarantee getting a bluff from him on river or a c/c for value from him when you c/b turn and bet all rivers.

You also run the risk of getting c/r on the turn which means you are like always drawing to just a flush and never getting paid off when you do hit.

All that said, yeah, check behind turn.