The EFG 250 / EFG 120 is not meant for important data

I loaded the device with two 250Gb drives. Taking advantage of the ability to mirror drives is one reason I really liked this device.
In the past 6 months the device has crashed atleast 5 times and 2 were critical. For some reason the device loses the abillity to see the backup disk. Once this happens you have no solution other then to format the backup disk. This is were the bugs kick in. Formatting the backup device will either work or cause you to lose all data.
Lynksys support is of no help. I have spoke to a dozen techs in multiple levels of support. They can offer no help except to walk you through the same 5 steps which usually do nothing to solve your problem.
I'm not sure how or if I will continue to use this device but I will say be careful and do not put it in a mission critical position. I trusted this device and lost years of data.