I've been wearing size M Jets with a 3 mm tropical bootie and they caused blisters on the top of my toes. I bought a pair of size L and put small spring straps on them and they flop around with 7 mm Tusa hard sole bootie. My foot flops around in the bootie as well. How can I make them work? Do I need Rock Boots? It seems silly to dive wet with Rock Boots.....