Advice Needed: Direct Vent or not? Indirect vs Direct WH?

I am in the process of adding a 2nd floor to my ranch home. I built a mech room on the 2nd floor so I could change the entire house from forced hot air (gas) to hot water baseboard (gas). I also want to change my electric HW heater to something more efficient. I am having a hard time deciding what type of boiler to go with. I was planning to get a high efficient direct vent (Peerless PI-140), but was told that it would make too much noise on the 2nd floor. I was also planning on getting an indirect-fired water heater, but was told that they are not efficient because the boiler has to run year round. If it makes more sense, I can always install a conventional boiler and WH. Any help is greatly appreciated!