nice oliver. i have looked at these before. olivers were nice because they had a motor set under the head stock, which really reduces the vibration. ball bearings will be nice as well.. You need to allow for some adjustment to keep things lined up. I like the 20c's rather then the 25 because it can have the motor swapped out like you did. I also converted my flat belt to a timing belt setup with a 3 hp vfd and 4 speed gear box. Are you planning on also adding a gear box ? I think you will find it useful and give you a better usable range of speeds.
lou