After I submitted the review, I received an email and several calls from the vendor, explaining that there has been some misunderstanding or mix up, and vendor was very friendly and pleasant. Quickly refunded the deducted portion (50%). Great and prompt customer service for a rather unpleasant experience. Have yet decide to purchase another unit (i.e. give it another try) or just go and buy one from a local hardware store.
I purchased a unit based on recommendation of a colleague at work. The unit was shipped and arrived on time. Upon the first try, the unit failed with very little amount of oil got drawn up (less than 100 mL in 10 minutes!). Did a vacuum test (plug the hose and pump several dozen times) and it would appear the unit has a leak either at the switching valve or connectors. Chose to return to vendor and it was such a bad experience. Postage required to be paid by customer (40$), and vendor chose to deduct another 50% stocking fee, claiming it has been used (Of course it has been used as we tried to use it to remove oil, Duh!). Sorry, can't recommend product or vendor. Hope your experience is better - good luck!