I think I'm a little off the wall here since I haven't seen this question asked this way anywhere else, but here goes:

Would anyone ever recommend replacing an existing gas/forced air heating system with a gas boiler and radiators for hydronic heat?

I know that all things equal, I would prefer the hot water heat... more steady, not as dry, not as noisy, etc. But here's my situation, I'm looking into buying an 1898 house that has existing gas/forced air. The furnace works fine, but it is old and will need to be replaced soon.

The easiest and cheapest approach is obviously to replace the old furnace with a modern high-efficency furnace and blower. But if I have to make any investment at all, how outrageous would it be to run plumbing instead of the existing ductwork? Near as l can tell, actual energy efficiency would be comparable either way. Is it possibly worth additional cost and effort to have more "comfortable" hot water heat? Or is it likely to just be too much cost and effort?

Any thoughts?

I'll tell you the story of my home. I bought a 30 year old all electric home with ceiling cable heat (expensive and not at all comfortable heat) and no A/C (no ductwork). If I had my choice I would have put in radiant hydronic floor heat. And a couple mitsubishi Mr Slim A/C units.

Baseboard heat is fine, but no comparison to the even, uniform comfort of the radiant floor tubing systems out there today. After comparing cost, even though I was doing it myself, and all the construction required to get the tubing around the house I opted for the forced air system. Also with radiant floor heat I would have had a thermostat in each room, since my living room, weight room and den are hardly ever used.