Just in case anyone else comes across this thread in their own research...
I've had the same experiences on primo. I grew so concerned when i first used primo that I thought the UGL put in deca or test. There was a decent amount of water retention and I got what felt like deca dick. Out of all compounds I've tried, primo has been the worst. 10mg Cialis just about makes up for it, but you're getting natty libido and sexual performance (not even trt).
Ironically, my libido and sexual function on nandrolone was amazing (as I found out in subsequent cycles). Even on tren, I can get and sustain an erection for an absurdly long time. Cumming is almost impossible though.
My thinking about why primo causes this was the same. (1) potential e2 issues or (2) primo displacing dht in libido/erection cascade.
I've done a blood test 4 weeks after adding 300 mg/week primo to a trt base of 125 test e/week. My e2 was where it normally sits with "trt" test (high normal). So if there are e2 issues, it's more likely to do with primo not allowing e2 to bind/act as normal (given e2 blood levels are unaffected).
The dht displacement theory is also a good one.
This is very sad as I get a lot out of primo. 200mg on top of trt test gives me a very nice, full "genetically gifted but not roided out" look. I can see the benefits in the mirror quite quickly, although I get some facial bloat which isn't great. If I happen to be running 5mg cialis for BP/pump and if I'm not very sexually active, I have thrown in 200 mgs primo towards the second half of a cycle just to get some extra anabolism at low health cost.
As a similar, dht based, low health impacting substitute, masteron is a decent choice.
I really enjoy masteron. Mentally I'm confident and stable; strength boost in gym (to equivalent test dose); libido and sexual performance is greatly boosted too; and there are a lot of aesthetic benefits (details like striations and veins come out). The two downsides are: it does tend to flatten me if I'm not on top of diet. Secondly, I am not sure how effective it is in inducing growth. I grew a on trt test plus 500 deca. I'm not sure I grew a whole lot on equivalent mast dose. (To be clear, I am comparing the gain in LBM 3 months after each cycle ended. Otherwise, it's hard to distinguish the bloat/water retention that deca causes from true LBM).
A cycle i enjoyed was trt test, some deca (400) and some mast (300). Deca tends to make me a little too chilled and lovey dovey and hippie like. Mast kicks up my motivation/drive up a notch to counter balance this affect. Also is a nice addition to any cycle for mood/strength. And I cross my fingers and hope that the extra aas mgs it is providing is translating to muscle growth. And at a lower cost to health than using all deca (700mgs) would have done.
Thats a lot of hoops to jump through to get "primo like effects" without primo libido sides.
