We're not exactly sure what you mean by the statement "the brochure is not completely accurate for added features and differences between Performance and High Performance series. We reviewed the catalog specs (pg. 30/31) and the following differentiation is called out:
1. Engine - Kohler 25hp vs. Kawasaki 27hp 2. Heavy-Duty Canister Air Cleaner - Optional on 74903 vs. standard on 74923 3. Drive Tire Tread - Turf Master vs. Multi-Trac (engineering tests indicate Multi-Trac provide improved traction and retain less dirt/grass). No difference in size.
4. Greasable Spindle Bearings - Ball bearings (74903) vs. Tapered bearings (74923) 5. TURBOFORCE Adjustable Baffle - 74903 adjustment requires loosening and refastening hardware whereas 74923 is tools free utilizing a cam lock lever 6. Deck Hanger System - 74903 utilizes chains vs. 74923 utilizes solid links.
Hope this information is useful.
-The Toro Company