I really love my Lunas. I can comfortably wear them all day, and feel them roll about when I do things like yoga, fast walking, stretching, etc. Exercising is fun with them!
I tried the Smart Balls and the Gyneflex system. The Lunas are the least intimidating of these and the sexiest/most atttractive
My partner noticed a difference after a week of use, which was way quicker than any of the other devices. I have pretty much zero complaints. I wrote a long review on them, but there are lots of good Luna reviews out there
Have fun and try a few and see what you like most!