Depends on what your current 6th option is I guess.
Personally I have three double rock Golems at L30. They all have poor IV's since they were all evolved from L30 Geodudes found in the wild. I do have high IV Golems at L20, but I haven't really been able to justify the stardust cost yet. Granted, Golems are great, but I'm really not sure I need more than 3 of them, even if none of my current Golems are stellar. But they mostly get the job done!