Possibly the only other downside is on those days when you decide everything needs a 'couple' of extra clicks (or less). You could end up giving a touch more than you intended going to 1/4s i.e. habit rather than conscious decision..
If you think MoA though, 15 MoA per turn on say a Leupold versus 9 on a Nikko really helps to avoid a turn out problem. But that bites everyone at some time.
BFTA Secretary 2012-2014
CSFTA Secretary 2014-2016