It depends on which lenses.


Bryan points out that third party lenses reverse engineer the communication protocol between the lenses and camera, so you're less likely to have issues on that venue with a Canon product, but otherwise....


All of my lenses are made by Canon, in part ouf of laziness and need for conformity. However, if anybody knows a third party 50mm that's canon L quality (without the quirks of the Canon 50mm f/1.2L), better than the 50mm f/1.4, and more durable, etc., please let me know.