I've only stopped talking PM completely, a couple times since I started, and it seemed like morning erections took about 2 or 3 weeks to return. I took this as a sign that my previous high sex drive/male libido was just around the corner, but I can't say for sure. Usually by that point, I could start back up so I don't know to what extent everything else returns to how I was pre-PM. I would imagine the timing would be similar give or take a week depending on the individual and the actual mechanism of action of the particular herbs one takes.
From everything I have read, the smaller size hoselover is reporting is from lack of practice/use rather than a direct result of the herbs. So, if he didn't want the smaller size, he would merely need to use it on a daily basis to maintain things. For me while on PM, I just don't even think about using the equipment anymore, and before I know it, it's been literally a week or two since my last erection. Like hoselover, I don't mind this at all.