Hi, I am going through this issue at the moment.

Are you sure it's the regulators?

My window gets stuck when it's all the way down. The way I got it up was by sticking a flat head screw driver in the corner of the frame to the rear of the window so it could slide up.

I am going to replace it with a clip that looks like this:
BMW X5 WINDOW REGULATOR CLIP FRONT RIGHT | eBay

I've heard this is a common issue and worth trying before replacing the whole regulator