I have a bunch in my inventory, and like them a lot. They are stupidly bright, and I haven't found the
zoom speed, nor the movement speed to be a detriment.
Then again, if you are expecting them to move as fast as a VL2500, or studio spot, you will be disappointed.
That being said, you don't say where you are from, and the fact that the VL3500 requires over 200v can be an issue for some in theaters, or churches.
Best bet is to get a demo from your local dealer.