I have used both styles of Wilson's "conventional" ambi safties, the tactical and the high-ride, and they're good parts. I don't know that I would go to the expense of their Bulletproof ambi, which is really nice but costs way north of $100.
I prefer the shape of the levers on the tactical, as they ride a little higher on the frame than most ambis, but more people seem to prefer the levers with the "knuckle" in the middle that allows the lever to ride a little lower.
If you are going to pay a 'smith to install it, ask if they have a preference.
I used to really favor the Cylinder & Slide ambi, and have three of those in use, but they require a lot of cosmetic work to look good, and that shouldn't have to be part of the installation process.
The Kimber ambi is a nice part, and doesn't require modification of the grip panel, as the lever on the right side is retained by a modified hammer pin.