It's usually only the front mount that needs to be replaced. It's not super difficult, just time consuming. You have to support the weight of the engine while you are doing it, so you need a jack that doesn't leak down, or an engine support bar. If you go the support bar route, it's helpful to have a second person to help install it, and adjust it while you are under the car. I tried to do it myself and dented my fender.
I have Pedro's Enthusiast mount. I think a lot of it depends on whether you want the car to be a smoother quieter daily driver, or more aggressive. You can feel engine vibration through the seat with Pedro's mount around 3,000 rpm. The stock Porsche mount is quieter, but probably won't last as long.
-james