As for the trainer... i bought a magnetic one last winter.
I dont know, it didnt seem to do anything except hold my bike in place and let me spin my back wheel?
Like... everytime i would switch into a harder gear, it would be the same difficulty.
i returned it and got a fluid one - same thing, so i returned that one too.
Maybe i got a bad brand or i'm too retarded to operate it... who knows.