I added 100mg/wk primo to my 150 test last years and I liked it. It's hard describe "what it did" but I put on a few pounds and stayed pretty lean. I don't think 100mg impacted my bloods at all if I remember correctly, and I'm pretty low estrogen anyway. For the price I like adding NPP better. I've never gotten some of the bad sides people get from nandrolone, and just 70-100mg / wk makes my joints feel great, especially if I'm dieting / getting leaner. I imagine I'm just going with NPP going forward, just added it back in 2 weeks ago actually for the rest of the year.