When you're asking how they compare, are you looking for answers concerning durability, crispness, feel, lock time or repairability?
Kolar-mechanical triggers
I have a set of Kolar triggers that have over 100,000 rounds on them and never had to do anything to them beyond cleaning. It took a short time when the gun was new to adjust to the "feel." (I'd been shooting Perazzi previously)
Lock time, about average. (my opinion)
Perazzi-inertia triggers
Have had several sets I really liked for the crispness and "feel". Have broken several hammer springs, but takes 5 minutes to fix. Perazzi makes a good trigger system in my opinion.
Lock time, about the same as Kolar as far as I can tell. No sure anyone can discern the difference in lock time between the two.
Hope this helps.
Dave