One is whether the company is still alive, having filed bankruptcy earlier this year, and how long they may be alive if they still are.
The other problem is even more serious. OnStream drives are not standard SCSI devices. They require proprietary drivers, which may work on some versions of some operating systems.
The company was founded by the same crew that produced the least reliable tape drives seen in recent times, Colorado. I suspect they could still have the same attitude on quality.
I wouldn't touch 'em with a barge pole.