I think the full bidding is needed to really determine this one. 1. Who is dealer? If South, the bidding starts 1♦ - pass - 2♦* (inverted) for the "3♠ preempt" to make sense 2. Was West dealer? If yes, Did North open 2♣ or 1♦? After pass - 1♦, I'm not sure many will preempt to 3♠ with a 6-card suit and 1 HCP hand. But after pass - 2♣, anything can happen. 3. If North is dealer, the same question arises. After a 1♦ opening, not all Easts will jump to 3♠ with ♠J109xxx(x) ♥10(x) ♦xxx ♣xx. But a 2♣ opening removes all shackles from East. Now anything goes I don't think there is any clear cut answer. 1. If East overcalled 3♠ after (west) pass - 2♣, I'd play him for the weakest possible hand ♠J109xxx ♥10x ♦xxx ♣xx 2. If East overcalled 3♠ after (South) 1♦ - pass - 2♦, I'd play him for ♥Q doubleton. 3. If East overcalled 3♠ after (North) 1♦, I'd play him for ♥Q doubleton. ... etc. I might be totally wrong on this, but I do not think there is a stand-out favourite line here.