Been using this service for a few days - both renting out my rigs and renting some extra hash power when required.
Very happy with the service - no problems what so ever other than 1 of my own making. I forgot cryptsy deduct the TX fee from the payment, so i didnt pay enough for the rig i wanted to rent so had to send a second payment. I raised a support ticket and got the first payment refunded without issue.
When renting my rigs out, Ive found payment to be without issue - yeah they dont come through the second the contract ends, however i didnt expect them to.
At the moment all of my 3 rigs have just been rented for 24 hours each.