I think I can sum this up pretty nicely:
1. barcons are probably going to be more reliable than STIs
2. STIs are probably going to last at least 10,000 miles (now admittedly I have the older model Tiagras, so maybe from reading the posts the newer models aren't as good).
3. Barcons, with respect to STIs, require more hand position changing to change gears.
4. STIs are better for placing your hands on the drops and hoods and being able to change gears and brake at the same time.
So the question you have to ask yourself: is the convenience of where you put your hands with access to braking and shifting worth sacrificing some measure of reliability?
For me it was simple; I love being able to have the freedom of changing gears and braking at the same time without changing hand positions as often. That of course, is not to say barcons are better or worse than STIs, just merely personal preference. As I said, if I expect to be in some extremely remote location, I might go towards barcons (but the more I think about it, the more I think I'd stick with STIs and just take some DT shifters for emergency use anyway).