I'm like you - started with X10 stuff and went to Insteon about five years ago.
My big thing is that my house was wired by idiots, and the switches aren't ever where you'd want them. Hell, the ceiling lights and fans in the bedrooms aren't even on the same circuit as the wall switch. (The wall switch used to feed a switched outlet, as the house was built without ceiling lights in the bedrooms.) Much of the split-level house is such that you're stumbling up or down stairs in the dark before you get to the switch you need. The ability to control a bunch of stuff from a single keypad at each room entrance was the one overriding feature. It's awesome, and I couldn't be happier with it.
My ex-wife never had any issue with the system (and in fact, actually installed a good chunk of it, being a fellow engineer). My current girlfriend, who is significantly less technically inclined, figured it out in about ten seconds with no explanation. But that's because it doesn't require web browsers or smart phones or other crap - everything you need is right there, right beside the door where you need to interact with it. Oh, and it's got labels, and lights up in the dark, so...
A few thoughts:
- One downside is that I had an entire generation of Keypadlincs go bad after about 3-4 years. All v5.x units, all killed in the course of a few weeks (power quality issues). Had six of them, so there's a chunk of change. Ouch. I found it interesting it only affected the 5.x units, however. Everything from earlier and later generations survived just fine.
- Insteon is unmanagable without an ISY-99 or 994. It just is. Best money I ever spent - now I just fire up a java app and can reconfigure anything I need in a few minutes.
- It's proprietary. If Smarthome ever goes under, I get to start over.
The rest of my automation is mostly telemetry. Temperature, leak monitoring, furnace monitoring, security cameras, etc. It's almost entirely based on embedded Linux boxes (RPis and older hacked Seagate Dockstars) scattered around, feeding data back to a central house server that then monitors things.