Iirc Derek doesn't use it anymore because he doesn't have time for topicals, but I think RU won't work well as a monotherapy for most people's hair loss, because he is on trt and therefore has higher test levels than most men, as well as that, he has used steroids in the past, so I think that may play a role in him being a responder
I think part of the problem might be Pg & ethanol tbh, it gives me dandruff flakes like Minoxidil does, I think k&b might be worth a shot, and might help out if u get irritable skin. I needle once a week in the morning & apply RU in the night and I've not had a problem, don't know if it would make it more efficacious tbh.
I've not seen a bell curve for RU, but I'd assume it has more flexibility in dosing than finasteride, so I'd assume the higher the dose, the better, if you have the money for it, I assume prostraken chose to trial it in 5% for a reason, but I think that may be because the higher the dose, the more RU is detectable in blood so increase risk of sides.
I've had no sides on RU from 6 months of using it, but I'm sure you know of the heart anecdotes and horror stories etc. I've done bloods on it, and it hasnt affected hpta axis or anything. I feel better on it than on finasteride, but I don't think it's as good for hair in my case.
Anyway, if you've got the excess money for RU I don't think it would hurt trialing it for a 3 month cycle. I think it is a decent adjunct if you are on 5aris, but I think it'd be too expensive to use it at a dose for monotherapy