I love Primo. I would cruise on it and Test forever if I could. I'm not sure it makes me feel good as much as it doesn't make me feel bad. I love Tren too, but heartburn, insomnia, etc. etc... Primo doesn't have those sides for me.
Relevant to the OP maybe, but I might be just a touch emotional when I'm running 600/wk of primo and 200 Test, or so, but that might be true of running any combination of things in the 600-1000 range, its the hormonfuckery. Cruising on 150-200 Test and 200 Primo feels like my sweet spot.