In reply to SenzuBean:
I have done several courses with Martin Moran. A winter mountaineer, winter climber and a Cuillin week. An excellent set up, good accommodation, good food (bring your own alcohol or buy in the village). I have had a mix with either Martin himself or his guides instructing me, always top notch. An advantage is accommodation on the final night, so it is not off the mountain and into the car.
Ratios are not fixed, it depends on the number of bookings, a 3:1 max will sometimes end up 1:1. I have not seen anyone complain of not enough mountain time, although a few moans about early starts, there will be some days with an 0730 start, but not all week.
I have no experience of other course providers.