As a medical assistant for an orthopedic surgeon (who specializes in ACL repair), a Professional Choice brace (or any soft brace, for that matter) is not going to give you anywhere near the medial/lateral support you need after surgery. You will most likely be fitted for a custom ACL brace - here’s a link to one brand: http://www.townsenddesign.com/Townsend_Design/Rebel.html
Donjoy is another brand that’s commonly used.
The brace will look similar to this although there also may be an additional strap going diagonally across the thigh. They are very rigid braces (I believe they’re constructed with carbon fiber).
There are hinges on the outside and inside of the knee. You may be able to put padding on the outside of the medial hinges to protect your saddle but I don’t think it will be comfortable to ride in.
PM me if you need more info. Your best bet is to talk to your doc at length during your next appt. and ask if you will need a custom ACL brace.
Best of luck with your recovery!
Taryn