I have the Sportscrafters model, the obsolete one with the composite rollers that are virtually the same as aluminum, with the exception that they cannot be used outside in sunlight or with the magnetic resistance unit(also obsolete?) since the rollers are not metal. This is my only experience with rollers except for 20 years ago when I used a cheap pair that was like riding on ice and I purchased the front fork unit so that I could use them.
As far as I am concerned the very positive reviews are accurate. I only purchased them to help with balance and smooth pedaling and use a trainer for conditioning, but am satisfied you can get a very good workout with them if they were your only equipment. Highly recommend.
This is the bike shop that has common ownership with Sportscrafters.
http://spinzonecycling.com/