Just purchased a Glidetrack Shooter SD from Alistair @ www.glidetrack.com. I cannot recommend this product highly enough - it is simply an awesome piece of kit, especially when linked with the Manfrotto 577QR quick release place and Manfrotto 701HDV head.
Here are few videos I have shot with it recently:
http://www.vimeo.com/17981477
http://www.vimeo.com/17979791
http://www.vimeo.com/17953967
