Personally, I like the Rebel better than the Switchblade, but that's a personal thing, others like Switchblade better.
They are targetted at similar riders I'd say. Switchblade is better unhooked, Rebel is not good unhooked. I think Rebel is a little better in the waves.
Some people don't like the 5th line of the Rebel, but I haven't had any issues with it and appreciate the ease of self landing. 2014 Cabrinha bar now leashes to a single front line, so the safety is pretty much the same as a 5th line.
The bar pressure on Switchblades have always been too high for me and turning too slow (again, personal preference), but I haven't tried the 2014.
Try and get a demo if at all possible! The first time I rode the Rebel I thought "This is the kite for me!" and everytime I ride a Switchblade I think "I can't stand this thing!" My buddy who flies Switchblades is the opposite, he won't fly anything else