Just one more voice about the differences in trainers. My husband and I have identical trainers (a year apart in age but same model) but for some reason the resistance on his is much 'tighter' than mine. He is definitely a much stronger rider than I am, but when we ride the trainer, I can always maintain a higher average speed which I know is not accurate.

For the most part, I don't worry about speed and/or mileage - I go by time in the saddle when riding the trainer and I do specific drills or intervals or endurance (steady HR) rides to keep my mind occupied.