uniballs are great, aside from having to keep them clean. lots of travel, fairly durable. just clean em once a week. however, heim joints make lots of noise. at least they did on my race car and it was easily 2k lbs less than my truck with alot less travel. they hold up great but if you dont like pops and light "clunks" heims are obnoxious. they are extremely durable though. the spc adjusts at ball joint, where as prg adjusts in the arms. just different, wouldnt say one is better than the other