Impact power question

I am saving my nickels and plan on buying an Impact in the next month or so. I will be ordering it in .25, but my power question is sort of odd. Does anyone have an impact with the .177 barrel and if so, can you shoot around 12 foot pounds without adjusting the reg? I ask this because I need to shoot Starlings indoors and would like to be able to have the .177 barrel for that and later on in the day swap to the .25 barrel and pop ground hogs at 100 yards with the turn of a few knobs. If I have to adjust the reg, its no big deal, but it would be nice if I didn't have to.
 
You shouldn't have to adjust the reg. I think you'll be able to get what you want done with the power and level wheel. 
Think of the regulator as a second air tank that's always filled to the same pressure. You wouldn't drain the air out of your tank to shoot at a lower velocity, would you? No, you'd adjust the settings that control the airflow after the tank. 
I think you'll end up at a very low power setting - maybe 1 or 2 - and a very low level setting - screwed in to around the first line. 
This means that the hammer will lightly "tap" the valve and then the level adjuster will knock it closed again real quick. 
I haven't heard of any .177's out in the USA yet. I've only seen the one that was in the video. You should get an incredible amount of shots from such low settings. You might consider going with the .22 and dropping it as low as possible.
Tom
 
The shot count is one of the reasons I wanted a .177. I have a Marauder with a hammer forged barrel in .22 that loves 18 grain JSB's, so I have an abundance of ammo for the .22 barrel on the Impact. It is just a pain to have to tune my Marauder for different powers. That's why I'm getting an Impact. I love the idea of bringing one kit with me and being able to shoot pest birds in a hangar and then 20 minutes later smack some large pests at 100 yards. I just figured a 12 foot pound .177 would be perfect for my indoor pest control because the trajectory is flatter than a .22. If I can't get a .177, then I'll be fine with the .22. I'm sure I'll end up getting all of the barrels eventually. .177 if they come out with it in the U.S. for indoor birds, .22 for my backyard squirrel extermination, .25 for my long range shots, and .30 just because I'm a sadistic SOB :)