I bought the Dyson Animal (purple/silver/gray) last year. According to the salesman, they all have the same size motor. That being said, the advantage w/ the Animal is the on-board tools and telescoping wand (which stores inside the hose. IMO, this vacuum is THE BEST. I have a medium coat German shepard and a smooth coat Jack Russell terrier. Both dogs shed year round. The JRT's hair sticks likes straight pins in my upholstered furniture. I purposely bought the Dyson to get the pet hair under control. (We had two cats as well, at the time of purchase). This vacuum does the job and it does it very well. Like anything that's new, it took a little getting used to, but I use it for all my floor to ceiling cleaning. I bought mine at Sears interest free for 12 months. At the end of 11 months I very happily paid the bill in full. If my Dyson met an untimely death, I'd buy another right away. I like it that much.
~ Kim
"Welcome the challenge...embrace it...don't fear it." - Cathe Friedrich