I ride a Merlin that I absolutely love, so I am firmly in the pro-Ti camp. I, too, considered Habanero but got a good end of the year deal on the Merlin and went with it.

As far as the Habaneros being built in China, they are made in Taiwan where the vast majority of carbon frames are made (not boutique brands like Calfee, though). So, I wouldn't worry about the build quality all that much. They know what they're doing. That being said, I do like that my Merlin (and my steel LeMond) frame was made in the US of A.

I do notice the Hab's geometry seems a bit long in the top tube, at least in the smallest sizes. My 49cm Merlin has a 52cm top tube with a 9.8cm head tube. The Hab 50cm has a 53.5cm top tube and a 9.7cm TT, which means a longer reach. I'm currently using a 80mm stem, and I wouldn't want to go any shorter as I could end up with twitching steering. So, in some cases there is only so much you can do with the bike's fit. Yes, you can change your saddle position (set back vs. straight seat post and rail adjustments) and stem (length, angle), but there are limits as far as feel, comfort and ride stability/control.

In addition to the custom geometry with Seven, you can also choose to go with double-butted tubes, which lightens the frame and your wallet. While I generally don't believe your typically person really needs custom geometry, aesthetically I like the idea of getting the head tube just right so no spacers are needed.

One thing I've heard about Seven is that they have a very specific fit philosophy. Such a philosophy may not fit with your body type or riding style. In particular, I've read about folks ending up with a geometry that they felt stretched them out too much.