Taipan veteran standard 22 regulator

I have a Standard, .22, and as you, I typically refill at around 150, maybe a bit lower. It's been a long time since I paid any attention to it, but it seems like I once saw it fall off around 135, which probably means it's set a little over that number. But I'm curious now too, maybe I'll shoot down the current remaining fill and see. If so, I'll post it here.
 
I could be wrong on this but I believe all Taipan rifles are factory set to 12 FPE to comply with FAC regulations. If they are shipped to the U.S., the dealer would be increasing the regulator setting and this could vary depending on who it was purchased from.

Taipan may have its own policy on this, but I don't believe there is any regulatory restriction on shipping FAC (over 12 fpe) rifles to the US. All the makers with which I am familiar ship all power levels to the US.
 
I just drained mine down to 150, shot it down from there. And yes, something around 120 is correct, as mine started falling off and becoming erratic at around 115.

How many more shots from 150 to it fell off ?

Depends on where you have your hammer spring set. My .22 vet standard was set in the low to mid 120’s. Bought it in 2017 and not from Talon Tunes. 
 
Guess they are setup with pretty high regpressure from factory, to make it possible to shoot both high power, and low power. I did install a huma reg in my .177 (since I also has a huma regtester, and huma being easier to adjust), and lowerd the pressure to 90 bar. Shoot now in 830-850 fps range with JSB heavy, and both accuracy, and shot count increased. With the factory setup the gun maxed out at 1040 fps with JSB heavy. Probably good for thouse which want to try really heavy pellets, but to much for my need.