Personally I would not worry about this. You only see the 'bad' on this forum and not the hundreds/thousands of people a day using 2-4-1 and redemption tickets who travel just fine. As others mentioned know your rights and know what options you may have available in case it does but I would not worry about it.
I had similar with a MIA redemption recently, looked very overbooked and was a full cabin but worked out fine despite me being convinced I would be offloaded....