Just a little update on my exp with the HF 90amp model.  I am now on my 6th or maybe 7th spool threw it and its been very frustrating at times since it just wont gen enough heat to lay flat welds.   Ive messed with wire speed and welding speed with very little success.  I have noticed I am getting good penetration but the welds will cont. to look like crap.  Either or for the price and the amount of stuff ive welded I would say ive already got my moneys worth out of it.   I am deff sticking with radnor wire tho.  So far its been the best at leaving less splatter and laying down the flattest.  Just a little fyi I guess. 
Heres a pic of a decent weld I made while making my bumper.
 I just finished making it today but I didnt get a chance to take some pics of it.  I wanted to make something diff then any else ive seen out there.