Yes, Ive got one and its pretty good. The desire holder is (alegedly) the same as the iPhone 3gs. I thinks its better than most offerings out there, holds the phone well - might even fit with something like the casemate barely there attached as they is a bit of "slop". It holds the phone well in my opinion. The bracket itself is fairly clever in as much as it has push button contols although in my car I cant quite get the angle I want. In my wifes car its fine although I would say it restricts visibility if you have a car with a small windscreen (that statement is based on using it in a Seat Ibiza vs a Land Rover Discovery). Overall I would give it 8.5 out of 10, certainly reasonable value.
Hope this helps, Jon.
HTC DESIRE DEDICATED SUCTION CAR HOLDER CHARGER KIT on eBay (end time 20-Oct-10 10:55:35 BST)