I was quite keen on this product when it first appeared, but then I read quite a few reviews which suggested that the thing was fraught with bugs, and was quite flakey. Bearing in mind the price of the product, and the fact that you're tied to a certain brand of AV software, which you still have to pay to keep updated, I decided against it.
If the main reason for changing is faster startup times and less load on the CPU, you might want to take a look at Eset Smart Security 4 - this uses pre-compiled code for faster running, and smaller memory usage, and they do claim faster startups. And for the price of the Gatekeeper Pico, you can have 3 years subscription
P.S. You can make your PC start up faster if you remove all the programs that you don't use any more, because each one will be loading modules and drivers in case you do run it, and these take time to load. You could also check to see if your PC supports hibernation or standby modes.
