The biker must decide according to the expectations he have of his bike, that is, there are important factors to us by either decant diameter as well:
1 - HOW WE USE THE BIKE?
2 - WHAT ROUTES USUALY DO?
3 - THE PATHS FOR WHICH USUALLY WE RIDE.
4- THE CONCEPT OF OUR BIKE IDEAL
5- DO WE CONSIDER THE AESTHETIC?
6 - HEIGHT IS A DECISIVE FACTOR OR NOT? ...
Personally I think one should try the bike with different inches, and as the sensations it receives and decide. Not because the manufacturers bet on some models, we must abide by it, as everyone has a different reality and as it will be better one way or another.
In fact, we can name different champions, and each uses a different one.
- ABSALAN: 26 "
- KHULHAVY, Hermida: 29 "
- And now NINO SHURTER championship in South Africa's 27.5 ".
What means this, that some are right and others are wrong? You have the last word, they made you decide.