Which is better: a 9.5 or 10.5 loft golf driver?

“Which driver loft would suit me?” is the real question you should ask. Loft is determined by many characteristics of your swing and the desired ball flight.

Lower loft can produce less spin, less launch, more ball speed and vice versa for 10.5* but it will drastically change from player to player.

You need to match your loft with your angle of attack, strike point, head shape (COG of driver) and shaft setup for it to produce “optimal” ballistics for you and you alone.  

Loft can also change face angle visual which can be a huge factor in a player’s ability to deliver a square face. Before you just swap the loft on your head get fitted for all of the above characteristics.