I got a snailmail invitation for the CSP with the 50K bonus after first use, did some research, and got the card. I'm thinking about getting my wife to sign up as well, although without the invitation she'll probably get 50K after a $3K spend, correct?

Every couple of years we travel business class to Europe, and we really like Lufthansa. Is the CSP a good fit for contributing towards these trips? Would we be better off with a different airline, given the CSP partners, etc.?

Is it possible to buy a Y ticket and use the CSP points to upgrade to C/J, or is that so inefficient as to be a waste? Is it better to just use points to buy a C ticket?

Thanks!