Went on another ride today with same results, better performance of Quest.
The shock is Kind Shock A5-RE 125mm length with 20mm of travel.
Finding someone to sell you the shock is the hard part. I ordered direct from China, shipped via USPS ( $5 US for shipping). the name of the vendor is AliExpress on the net at http://www.aliexpress.com/store/product/KS-Rear-Shocks-for-Downhill-Bike-Mountain-Bicycle-Rear-Shock-125mm
?Maybe CRUZBIKE could order a load of these and make them available as and upgrade for current Quest owners.