>>3354097X-Tol has finer grain and gives more shadow detail. Nothing drastic, but it's there.
Also it's less contrasty (in the highlights), HC-110 is a very active developer, sensitive to agitation, and it's easier to block the highlights.
So all in all, X-Tol pushes better.
There aren't any mindblowing differences, you'll see the most difference when pushing.
HC-110 was engineered in the '60s to give short dev times and long shelf life, which it does perfectly.
X-Tol was the latest general purpose developer, engineered for low grain, shadow detail/pushability, accutance and eco-friendliness. It has all of Kodak's R&D poured into it. However the disadvantage is short shelf life (6 months).
Economy is not much different I think. HC-110 is ~25-30$ for 1L, at 1+31 this can develop 100 films in a small tank (300ml).
Xtol is 12-15$ for a 5L bag, at 1+2 it can develop 50 films. So 2 packs (24-30$) give you 100 films.
I like Xtol cause it's economical and really flexible, you can use it in "fine grain mode" (stock), or "accutance mode" (1+3), and it will still give you full speed and better accutance/grain balance than most developers. Also, it works with any film under the sun. It's an improved D-76 essentially.
HC-110 is tried and tested too, and it works well. Use whatever you find more convenient, there are no huge differences.
D-76 there's no use to try that, if XTol didn't make much difference. D-76 is Xtol's grandpa, technically there isn;t anything D-76 does that XTol can't do better.
Microphen is nice, pushes really well while keeping grain and contrast in (relative) check. Works great with HP5+ and cubic grain films in general. Gives half a stop of true speed.
