Yeah, the $30 pico will work... but it still seems like a crutch for a simple problem. A good example is the game room upstairs in my house has a short hallway leading to it, with it's own light and switch. The only time I ever use it is on my way to the game room. With Insteon I just linked the two. I hit the light on the way in and the game room lights too. So, yeah, I could carry a pico for that, or put one in the wall in a two-gang setup and it'll work fine, but it's not really the 'best' solution.
Going through this exercise has sort of impressed me more with Insteon. I mean, I'm still having some mild communications issues and reliability issues that we've all heard of (which is why I'm exploring RadioRA2 in the first place), but it's super flexible. I use a great piece of software (Indigo) to help manage the network and it provides a very high level of flexibility.
Another great thing is the ability to have a 'double tap' on a switch call a second action. (i.e. tap 'on' to just turn the light on, but if I double-tap it, Indigo will then dim the light, and turn on a couple of lamps too).