I just did a second replacement, first was a Style II. There is a problem with the flush pedal and would not recommend to anyone, replaced the orginal plastic tilet with thatt one. This time I used the 510H. Easier replacememnt because I had already switched the bolt placement. The old one was at angles to the front, the new parallel to the front, (9 & 3 o'clock) I had enough flex from last replacement to plumb right up.
China bowl is a lot better.