I am running a 36-60-2000 in my Ofna MBX conversion on 4s and it runs nice and cool, never got above 150. I think you should be fine on 5s, just gear down some.
im happy everyone is happy with the Medusa 60-2000, i should have mine next Friday, along with my tekno revo conv, 4s 5ah, mmm, hyperion.
Any recommendation on gearing for my conv?