i don't think the diverite fins have a particularly high sidewall, but i use them to back kick pretty briskly. It's just a matter of technique.
my concern with the X1 fins (that i didn't realize until i bought some) is the downward bend of the blade at the toe will reduce how wide the blades can go before the power stroke of the frog kick. For this reason, the fins have been hanging in my garage for over a year, never wet. I think you really want something that is flat - like the jets and such, also the divert fins and mares quattros, all popular and very effective for all the kicks you'll want to use for technical diving.