Radiant Heating in floor

We are in the process of deciding if we should go with forced air heating verse radiant heating in between the floor joists...for a cabin that we foresee in living in year round.

Question about the difficulty in the actual installation of the plex piping...things to watch out for... the number of zones one should have for a two story 1500 sq. foot cabin.

Dealing with non potable water has promoted the thought of using two hot water tanks , one for tap water and the second for the heating of the cabin... in particular if it would be possible to maintain the house heating tank with a combination of city water and gychol in a closed system? What size of tanks would be advisable to get? Should they be electric or gas? Any maintenance to the system required?

It was suggested to me that I should be considering the use of a boiler verses hot water tanks... Pro's and Con's... I have heard repairs to a boiler system can be costly besides a high cost factor initially to but the system in.

It was suggested to me that I need still need to have an air circulation system installed to help move the air around? Is this so...? Meaning duct work...? or is there an alternative?

If there are any other items that I should consider... I would appreciate your thoughts.