Gearing change
 

I have a Trek 5200 with a triple (53/39/30) and a 12/27 cassette. I'm thinking of switching this to a compact setup as follows:

FSA compact crank 50/34, custom Shimano-compatible cassette 11/28. This gives essentially the same range as the triple, but with less duplication of ratios, the simplicity of a double, a little less weight, and--the main motivation--fewer double shifts.

I have the FSA crank, but am confused about what I'll need to buy:

1. Can I keep the triple front derailleur?
2. Should I keep the long cage rear derailleur? Will a short cage work?

Any comments on making this switch appreciated....

Front derailleur will be fine. Keep the long cage rear derailleur.

Sounds like a good change.