The twin westpack hasn't got the best wand head design! I never liked it when I had it.
The westpack 4 jet is alot better though. Lowered angeled jets to dig in to the carpet and a shorter, better angled head that had airflow efficiency. Thts what i reccomend. Make sure you get the 2"inch cuff converters for it though if your using a 1.5inch hose, has the wand is 1.75inches.