It only actually uses reflection if you choose to -- you can avoid it entirely if you don't want to use the property-path-based bindings. Additionally, it cach

It only actually uses reflection if you choose to -- you can avoid it entirely if you don't want to use the property-path-based bindings. Additionally, it caches the reflected information, so that it's not constantly doing lookups for the methods that make up properties -- just the first time a particular property is seen on a type. This cuts out a huge amount of the time spent on reflection, and it generally is a tiny portion of time compared to the amount of time it takes to build and render the UI. I've found it hasn't caused performance problems in my app at all (usually the layout is the most expensive part of the UI).