One of my concerns before I bought rollers was whether I could get enough "resistance" when I wanted
a resistance, as opposed to a spinning, workout. I bought Kreitler's with the killer fan. Believe
me, there is all the resistance you could ever want with that combo.
Not only can you vary resistance by changing your gears, but the fan itself can be adjusted to vary
its resistance. You can make it _very_ hard to turn your cranks, if you want. Also, because you're
really riding/balancing (which, btw, takes more focus than on the roads, and obviously on a trainer,
because steering is so sensitive) it's less boring than a trainer.
In the beginning I had trouble riding more than half an hour because my tail would get so sore. With
it taking my full attention just to stay on the rollers I didn't dare try to stand. But to get in
the longer workouts I wanted I knew had to force myself to stand to get tail relief. I had some ugly
moments but I got a handle on it. And now that I can ride as long as I want to.
I have no idea whether the skills you have to develop to ride rollers translate to being a better
road rider. And I wouldn't argument which are "better", rollers or a trainer. But if you're worried
that rollers are just for a "light workout" forget it. You can make it as "heavy" as you want.
--
Jim Rech