Yeah, a 13x4 on 4s should be great for slow work but will lack a bit of speed. I guess it depends what sort of flying you like to do but I'd recommend at least trying the recommended 12x6 on 4S as it's a pretty good setup all round.
If you want to really make the thing rip use a 14x7 on 4s with a Motrolfly DM-3615 750kv, this is my EF laser but the Edge performs just the same: