25.5" guitars are ubiquitous, so go ahead and give it a try.
The thinner the string or the longer the scale, the lesser the measure of string inharmonicity due to tension. It doesn't really have anything to do with the pickups, the string will eventually just sound shitty if it's too thick and too short. Each person has their own limit, but for me, it's around G on a 25.5" scale. Going to 27" helps this two-fold. 1) The string is longer, and 2) You can get away with a slightly thinner string. So at 27", you can tune down to F# and even F with it sounding better than 25.5" at G.