to be honest, i of course spend a lot of time on the groomers, too...
for example is simply lame in terms of groomers. i mean, it's probably a place to ski with young kids or so.portes du soleil
is very very big. grooming is crap until after new year (because the french operators know that customers come anyway, so why care?), but gets better later on.davos in detail
: the 350kms of grommed slopes are split into 5 seperate mountains. parsenn is by far the biggest and covers huge acreage, but not as many slpopes as one might think. very little challenge, too.
rinerhorn is unreliable in terms of snow.
jakobshorn essentially is a 180 degree skiable montain, all above treeline. the grommers are a variety of red high cruisers, great for carving mach speed. quality grooming, best lift system in the region.
madrisa is a family resort, nice offpist eto be had, but the groomers are nothing to die for.
from what i have seen from st. moritz
so far, the skiing is very good. the grooming is excellent. the village itself has a noth-facing mountain and a south-facing one, that may come in handy depending on snow and weather.andermatt
has 2.5 mountains with relatively few groomed runs. one of the most famous expert runs in the alps, though. but you will not go to andermtt for groomers alone, really.
other big resorts to consider in switzerland: flims/laaax (south-facing, famous for carving slopes), lenzerheide (large intermediate resort), grindelwald/mürren (jungfrau region, super scenic) engelberg (gets lost of snow, huge vert), crans montana (can be super crappy as it faces south and gets little snow, what a sombination)
one last word: if you want to have equally good groomers, lifts, offpiste, snow etc...you may need to cross the border and visit ischgl in austria. ischgl is basically the only resort where i wouldn't relly mind if no offpiste was available, since the groomers are that much fun. i couldn't say that of davos. i think st. moritz will be as good, but look if it has enough natural snow.