ReadyNAS 104 system hanging frequently after 6.4.0 upgrade

I've the same trouble.  1 x RN102 w/2 WD 1TB Greens, and 1 x RN104 w/4 WD 3TB (2Green 2 Red).  The 102 seems to be doing better after doing a full factory default reset (all that was on it were personal Time Machine backups), but haven't really tested it hard yet.  The 104 tho..  Hoo boy.  Locks up during boot, locks up when sitting still doing nothing, locks up when accessing from work, locks up when looked at by my cat, locks up when trying to copy data off the NAS to my external HD (hooked directly to the NAS), locks up when trying to access it thru my Xbox 1, etc.  Basically, it just locks up whenever I try to do anything with it.

Right now, I'm having slight success while copying the 104 data to an external HD hooked up to my iMac (SMB seems to work much better than AFP), but it's touch and go.  I tried reflashing the FW, as well as reinstalling the OS, but both to no avail.  I deleted the snapshots (and managed to save close to a TB of space) as recommended, but that didn't do anything as well.  As a side note, I turned off COW as well..  Now I shouldn't have creeping data on my free space after a defrag.

I tried downloading the logs, but it locks up :/

The unit was flawless until the 6.4.0 updates.  When I performed the updates, both units locked up on rebooting (no activity on the drives).  I had to reflash, etc..

I think I had to just vent a bit.  They're not for business use, my NASes (NAE?  What should be used for plurial?  Lol..) are just home units, and while taking the time to copy everything off the units to reset/default is annoying/frustrating, it's not crucial..  Unless it eats my data, then it's not good.

I'm keeping an eye on the forums to see the progression of people's problems, and hopefully Netgear will have a solution for this quickly.  If the reset to fac. defaults does not help in stability, well..  I hope they come out with a new FW quickly!