Water quality is always the big concern when dumping water. If the water has high mineral content or something else, it can clog the perf in the recharge well or the dry well. Cooling or heating the water can cause the minerals to come out of solution and clog the perfs or sand.
If your water quality is such that it will not clog the dump well, then either type set up will work. The deeper wet well would allow you to install a longer drop pipe and the siphon effect will reduce the head and power used by the supply pump. But a few feet of difference is not going to change much. Also if the well clogs and stops taking water, it would be easier to work on the wet well as the other one would be covered up.