While not an expert like many of the techies here, I feel the Biopace on my tikit improves hills climb performance. By virtue of its shape, you can actually feel that the ring is NOT round when you climb - and its weird shape actually seems to help transfer the power and improve the "rhythm" of the pedalling cycle.
Hope I'm making sense? My Speed Pro too has the Vista Sycnro chain ring which is similiar to the Biopace. The top Dahon riders of my club seem to agree that it helps esp in the climbs too.
http://www.vistadeal.com/En/Produits...au_Synchro.php
Guess at the end of the day, it boils down to whether you agree with Sheldon Brown's analysis and I for one hold his views in the highest regard.
