I would recommend any strain found by John Allen. Or, even go for THE John Allen strain (available on spores101), because it is a fairly easy cultivation and is very contamination resistant (so the site says). An amazing, intense strain is Penis Envy, developed by the late, great, Terence McKenna, so you know it's gotta be amazing (which it is).
I've never personally grown (yet), but I have had Penis Envy, and know that it is an incredible strain.