Rough stats, for guys balding from an early age of late teens to early 20's, AKA aggressive male pattern baldness:
Chances of getting no impact at all on both minoxidil and finasteride: 20%
Chances of simply maintaining hair with both minoxidil and finasteride: 60%
Chances of re-growing hair on both minoxidil and finasteride: 20%
It is not very likely to regain hair with any treatment (apart from hair transplant of course), unless it's aggressive and dangerous drugs (and you want to have tits). Where are you getting the idea that there's a great chance of this happening? 20% is probably an overstated estimate, its for the lucky few.
As for my experience of minoxidil starting age 24, now I'm age 28:
Used for 6 months, got some density back, no movement on the hairline. Stupidly I stopped using it for 2 months, being clueless and as mentioned, stupid, I thought I could just pick up where I left off anyway. I lost any density and probably more hair than I had before starting.
Of course I started again. From there, 6 months or more of very little, and probably not noticeable increased density (nobody ever noticed as far as I know) until just maintaining for probably a year, and then, another year or two of facing up the the fact that I was losing hair at the same pace as before being 24. If I hadn't have stopped for those 2 months, I probably could have had better re-growth, but not for long.
minoxidil was no longer doing anything, which is inevitable. If you are one of the lucky few (way less than 20%, which is minoxidil AND finasteride) to get any growth from JUST minoxidil, you'll need to keep rolling that dice and hope you never luck out, but more than likely you'll need something else within a few years.
So effectively what's the point? If minoxidil alone is only going to last a few years, maybe 5 at the very most, why not just go on finasteride as well? You're only stalling the inevitable, and in that time you could have seen more growth while on both anyway.
Starting on finasteride at age 28, nearly 5 months ago, increased density, the little "island" forming at the front is now joining it's friends at the temples again, I believe the hairline is advancing slightly, there are positive signs such as the middle of my hair gaining vellus hairs a centimetre down my forehead (so in hope, I think this means the hairline across the board is advancing) and damn, why the hell didn't I start this 4 years ago?
Don't waste your time, mix it with finasteride, if you get sides which is very unlikely, stop taking finasteride and you'll get your boner back, and then mix it with some of the other drug treatments out there. But if you think minoxidil alone is a permanent solution, no. Just. No.
If you think that, you may as well just give up on minoxidil now and begin facing an early life of baldness, otherwise, come to the realisation that you'll eventually be on finasteride soon anyway, and just start taking it.