I've got the best 2 channel system I can afford. A surround system wouldn't sound optimal in my living room due to the room's physical layout (nothing I can control - I rent).
A great dealer steered my away from HT a while back when I was trying to put together my first 'real' system. He asked what I watched and what my budget was. I could have afforded an entry level Arcam HT system and a Totem speaker setup which sounded great, but it wasn't my best option. I watch sitcoms, comedies, and sports. Not much special effects or serious surround info there.
I bought an NAD and PSB 2 channel system that sounded better for music and my video needs. Better to spend your money on two great channels rather than 5.1 mediocre channels IMO. Not that the Arcam/Totem combo sounded bad at all. I got higher NAD and PSB gear that I could have afforded with Arcam and Totem. And I saved a few bucks too.
I've moved on from that system, but the principal is the same - buy the best and least complicated gear I can for my budget. I'm so much happier with my Bryston/Rega/Audio Physic 2 channel system that I'd ever be with a similarly priced 5.1 system.
My system resides in my mancave that includes a nice flat screen TV, Xbox 360, and 2 comfy chairs. It doubles as my workout room (Total Gym machine tucked away when not in use).
My living room has a TV with no stereo hooked up to it. I've contemplated hooking up a 2 channel system to it, but I'd rather put that money into my main rig and/or buy more music. My wife could care less about a stereo in the living room. The computer and stock speakers that came with it are more than enough for her background listening.
When I move, if I to combine the main rig with the living room system, there won't be any serious issues. If I need to consolidate, the Naim Uniti may very well fit the bill. It sounds great too.