My new 5er has the built in unit and it does well. But I also have a Hoover nano, the beater brush is great for dog hair and it gets pretty compact and easy to store in the RV. A friend bought the Dyson DC35 when it was on sale for 200 bucks. She says its been doing a great job in their RV with 3 short haired dogs to contend with. I am just not convinced it would do so well with my long haired Australian Shepherd.