If it were me I'd go with the 2019 SystemSix. I love BMC bikes too. But that seems like it's priced too high. The Chinese wheels can be hit or miss. I know people who have ridden them thousands of miles with no issues. And I know some who have had nothing but problems.

Honestly I don't think any of them are bad choices. The two Cannondales seem to be better buys to me though. The 2019 SystemSix is a $4000 bike and you are getting it almost half price.