Upflush toilets differ the most from standard toilets in the discharge system. Upflush toilets do what their name implies, and discharge waste material up to the drain pipes above. Upflush toilets do come with their own limitations and problems.
You can't dispose of certain items in an upflush toilet that my otherwise pass successfully through a standard toilet. Tough materials, such as female sanitary items or even condoms, that are dropped in the upflush toilet, may cause a clog.
Using cleaning products outside of the manufacturer-approved list may expose the unit to cleaners that contain corrosive chemicals and damage the upflush toilet's macerator unit. Certain bowl cleaners that contain hydrochloric acid may eat away at the unit's rubber parts.
A problem you may encounter before even installing an upflush toilet is that upflush toilets are not allowed to be installed everywhere. Local plumbing codes may forbid you from installing an upflush. Consult your local plumbing and building codes to learn whether one is allowed in your home.