Interesting thread. Ive been considering getting a set of rollers as the winter months set in for some 'quick' exercise and to keep my lungs and legs since the prep and cleaning associated with winter (MTB) rides takes an amount of devoted time that I don't always have. I recently built a fendered single speed road bike that should see a good amount of use this and future winters when schedule allows. Again, added time suiting up and then wiping the bike down post-ride.
I'd imagine rollers are good for a quick spin at night when bundling up, burning the lungs, then cleaning the bike and self can be difficult to initiate. They should help for practicing balance, smoothness and pedal technique as well I'd assume (better than with a trainer).
Hopefully to add to rather than derail this thread (only my best intentions,
embankmentlb) I, and I'm sure others, would be interested in hearing/reading how those who use rollers to supplement regular riding (perhaps more often in the winter months) use them. Get on and spin? Intervals? Sufferfest or similar? (never used this series but assume it may apply) Catch up on your favorite soap operas?