Electric cutouts anyone ?

Are these electrical switched cutouts working good ?
http://www.mccordcg.com/mpp/order.htm

or

http://www.badlanzhpe.com/index.html

Any one familiar with these systems ?

I have tuned cars with them installed and without a tune most cars if EFI have power problems. Carbs are usually over rich enough that the cars run fine with the units open but on a EFI car I make a second fuel map on the P.M.S. systems to rich the car up or the cars are slower from going lean and no back pressure seems to cause power issues. Cars like back pressure and if you have no Cats and bypass the mufflers the cars seem to run slower and build less power.

Even with supercharger ?

Supercharger makes things worse. You are trying to push more air thru a larger opening which causes a bigger lean condition and without a tuning device that operates or tunes for different boost pressure you will be lean by 15%-20%.