OP I have run DINAN, ESS and now currently VELOS.
They all have their benefits and improvements on the M model for the X series.
From mild to wild this is my ranking:
ESS and VELOS in my opinion provide the biggest response in the mid range. Velos seems pull alot harder than the ESS and DINAN tunes above 4k RPM.
When I switched from ESS to VELOS it was merely I just wanted to see if the numbers provided are valid and I wanted something a bit more aggressive. Please note, I have not dynoed the car so I am only going off my butt and feel of the vehicle. Personally, that is all I care about.
I love DINAN and ESS. My E90 M3 is ESS SC and all Dinan drivetrain, suspension, interior, etc.
I have been wry happy with Omar and Velos. Just got a goodie in thesis today from OMAR!!! See pic attached!!!