Yeah, I'd go for 10GA wire, especially considering the Logans tend to like juice. Good call for not buying into that salesman's BS. Just out of curiosity, did you see the article where someone took apart a Transparent cable? If you search around, you'll that one, and it's really funny. However, I'm still not sure if MIT cables are any better, but it's still entertaining to see what you get for 10k when you buy Transparent.
Also, if you ever decide that you need to add some *BLING* to your system, you may wanna check out some cables from:
River Cable
Cobalt Cable
If you need more cabling, but don't need fancy looks, then I'd look into getting some stuff from either:
Blue Jeans Cable
Impact Acoustics
Many of the products offered by River Cable and some by Cobalt are actually identical to those offered by Blue Jeans, but simply not as pretty. Lastly, if you want make your own speaker cables from the Canare 4S11 cable (the same one used in the River Cable StarFlex SPX), I'd suggest that you head over to
Westlake Electronic where you can get it for $0.63/ft, as opposed to $1.05/ft at BLue Jeans. Be aware though, because the 4S11 uses PE insulation, it shouldn't be used for in-wall installations.
Hope you enjoy your new system!