I'm far from convinced you need a crankset. Chainrings take a long time to wear out. Most riders never have a worn out chainring. And if you did, you would probably be fine replacing the chainring, not the whole crankset. This is not a normal response to a worn chain and cassette. Unless you've left something out.

If you do need a crankset, well, if I were choosing between those two, I would get the FSA. I would be embarrassed to ride a bike with that Tiagra crank. What are these people thinking? I'm sure it works fine, but even I have aesthetic standards.