I think it depends on where you wanna mount it.
And that depends on what kind of gun it is.
To my long range 6,5 rifle (Tikka T3) I have mounted it 12 o'clock
I really like that postition for that kind of rifle and I can easaly reach the T1 regardless of shooting from prone or any other position.
Here is the T1 best mounted with an A-0003 picatinny rail.
For some really big scopes like I have a 6-24x72 on my TRG 338 i prefer the half past one position as the scope is so big that my neck not can reach the aimpoint if i mounted it 12 o'clock.
Here is the T1 mounted with either picatinny rail A-0003 or T1 interface A-0025
For the AR where I only use the T1 to shoot fast at short distances i prefer the 5 o'clock position as I then can maintain my checkweld when rotating the gun.
Here is the aimpoint mounted with T1 interface A-0025