i can only speak from personnel experience.
bullydog simply works for me and i like the ability to adjust on the fly. combined with quad to bump up rail pressure, setup works for me. bullydog has been helpful on tech support in the past.
as far as others, edge with a2 was in for warranty work 3 times. many deaths along freeways and such. they ceased to fix the parts so the parts were disposed of.
had considered smarty but had a few questions prior to purchasing one. sent pm to mr wagner, no reply, so not going on my truck. a quick check of my signature would seem to imply that i am not afraid to spend some money on my truck, but i am often wrong.