Well, just as similar to US domestic Y to F, the only difference is you get free food in Y.
The only benefit for CA B-738 F vs Y are:
1. little wider and better seat pitch in F.
2. Upgrade Food.
3. Early boarding and sometimes priority baggage service.
and ..
If flying in/out of CA' hub at remote gate, you will get premium bus/van transfer instead of crowded bus.