Originally Posted by Brian Ratliff

I have both a fluid trainer and, well actually 2 sets of rollers, one small-ish diameter (3.25") and one large diameter (4.5").

Most of my winter training is done on the 3.25" roller and consists mostly of just long-ish rides. I got really fit (when I was a road racer) and had my two best road racing seasons doing 2 hour rides on those rollers 2-3 times a week with a 4-5 hour ride on the weekend.