The only issue I have with Flexraid is that its basically one guy programming it and doing all the support. Nothing against him, but that means he's getting pulled in a lot of different directions and so he can't respond to support requests as fast as you might expect. I installed Flexraid about two weeks ago and I kept having an issue where when my WHS rebooted, the trial license seems to disappear and hence the drive polling does not start running and my shares are nowhere to be found. I have to re-request a trial license each time, then manually restart the service (and yes I did set the task up to start the service on a reboot). I posted on the forums there and I had to bump it twice before he responded (not mad at him mind you, just the reality of a one man show) and so far no solutions/fixes have been proposed.
Well, last night, I guess my 14 days were up because when I tried to re-request it, it told me the trial period was expired. I went ahead and purchased it to see if maybe adding a real license will fix it, but I don't know (hopefully I'll get the license email by tonight). If it doesn't, I'll try reinstalling. If that doesn't work, hopefully he'll give me a refund and I'll look at other solutions.