Like any treatment that helps regrow hair or prevent loss it has to be taken "forever" to maintain its benefits... This is true of minoxidil and propecia, or any other treatment you believes works. Instead of hearing that and saying " I should get on that now to maintain as much hair as I can" people avoid it saying they are not ready to commit to a daily spray (or pill) every day, forever. Once you are to a point where your hairloss bothers you enough to commit to taking a treatment forever (or until you don't care anymore) then there is no good reason to not start minoxidil.
There are issues of convenience, as over the counter minoxidil sucks (its greasy and messy, and makes your hair clump together, and takes a long time to dry). This can be avoided by using dr. Lee's minoxidil.
Some people talk about shedding with propecia and minoxidil... I personally take these posts with a grain of salt because 1) this is a hairloss site, and people here are having more trouble than most or they wouldnt be here 2) this is a hairloss site, so people who start the meds are already losing their hair 3) no photos are posted, usually 4) studies show these meds are good for hair. male pattern baldness causes hair loss, not meds (in general)
minoxidil and propecia have the biggest studies behind them, with 5 year followup for both showing treatment preserved more hair than placebo. I cant think of any other treatment that can claim that level of proven efficacy.
The 5 year study on Minoxidil ...
http://www.hairlosstalk.com/download/mi ... esults.pdf