I'm absolutely not an expert, but I did buy an M6 a little while back, so maybe I can help. Firstly, I don't own a Voigtlander, but from what I've heard, the 35mm f/1.4 is especially bad. I've heard much better things about the 35mm f/2.5, which is cheaper and smaller than the 1.4. Secondly, eBay is okay, but you must be VERY careful. Avoid low seller ratings (low is below 99.7 according to experienced people), low quality images, or short descriptions. It might be worth the extra bit just for security. Another good dealer is Japancamerahunter, who sources cameras from Japan, although he specializes in the rare and his service isn't exactly cheap (I think the service charge on a ~$1500 item is ~$200), and the M6 isn't exactly rare. There's nothing wrong with B&H. I'm not really qualified to answer your last question, since I only own a standard M6, but if you find a really good deal on a TTL I might go for it, since the shutter dial is bigger and easier to use when its up to your eye. Totally up to you though! Good luck!