If you go with Pentair, they sell automation bundles (controller and SWG) and then others with pool/spa actuators as well. So you get a bit of a price break. But there are two other great benefits buying/installing all at once.
1. If the Pentair gear includes three specific components, purchased and installed together, (same invoice), everything else Pentair purchased and installed together gets a warranty bump to three years. That can be a big deal, because not much of what you buy comes with less than a four-figure price tag, and if any of them poop out in the first three years, that's a chunk'o'change.
2. The SWG will need a power supply. When you buy a bundle that includes an SWG, that power supply is built-in, inside the controller's chassis, nice and neat. That same box will also house all the circuit breakers for your pool. It's a very clean-looking setup. If you don't bundle, and later add on an SWG, you'll have to either bolt a separate power supply box onto your wall, with a big ugly conduit connecting it to the controller, or try to have a transformer and surge card installed into the controllers box.
Buying everything up front, and installing it all as one, really is the way to go. And the "necessity" of an SWG is something you realize only after not having one, and then eventually getting one. Virtually everyone that ends up with one swears they'd never give it up, with their only regret being they didn't get one sooner!
