After the responses I'm a bit embarrassed to say that I did neither of those things, but bid 4C, thinking there is a good chance partner will give preference to diamonds if she has two of them, or rebid her hearts if she has a very good suit. In the event she raised to 5C which was passed out. The full deal was:
986
9
AK8543
AKJ
AQ4 KJT732
J862 T5
- QJ962
QT8753 -
5
AKQ743
T7
9642
Despite the 4-3 fit, when dummy came down it looked like the contract had play, although I was thinking it would be better to be in 4H. As it happens the 6-0 club break and the 5-0 diamond break put an end to any hopes of making, and I went two off for a near bottom. A heart contract can be limited to eight tricks on double dummy defense but those in hearts were making between 8 and 11 tricks. If I had managed to escape for one off it would have been a near average result. Note that if I double 3S and partner passes I will be putting 3SX= into the bridgemate.
I did consider both 4D and 4H but tried to be too clever, and paid the price.