Yeah, my first thought was curiosity about their volume needs. DB based queues are fine if you don't need more than a few messages a second of transport. For that matter, I've found Azure's Storage Queues probably the simplest and most reliable easy button for queues that don't need a lot of complexity. Once you need more than that, it gets... complicated.

Also, sharing queues for multiple types of jobs just feels like frustration waiting to happen.