Electric exhaust cut outs

Hey guys, I have a 68 Cuda,340s. I am in the process of updating my car after 21 years and putting in another motor and will be installing my TTI headers. I am interested in putting in electric exhaust cut outs. For those of you using them, what would you recommend I should look at. Are they worth it and do they work good? Power gain? This is a street car but I would love to flip a switch to get that sound and power they provide. Any suggestions or thoughts on the positive side would be appreciated.
Thanks
Sparky
I tried them for a bit but like the others I found them to be not very durable. I took them out and just unbolt dump flanges now if I want to run open.