I've been using only Version 2 units, mostly because they have the most RAM and work well with the FULL DD-WRT with all the bells and whistles.  

I have strived to get version 2 units for HSMM-MESH, however it occurs to me that since HSMM-MESH has a much smaller footprint than DD-WRT, I may be able to get away with using the other version units that have much less RAM.   Hopefully this is true, because the ver2 units are getting hard to find.

Any input as to what versions work well with HSMM-MESH?