Hi @slh, thanks for the quick reply. After some further research, I've purchased an MR8300 (I also considered the newer MR9000 but it doesn't seem to have support yet: Support for the Linksys MR9000)
In preparation for flashing, I am trying to find the most stable release for the MR8300 and have checked both the tech data (https://openwrt.org/toh/hwdata/linksys/linksys_mr8300) and table of hardware, which both list a snapshot. There doesn't appear appear to yet be a stable release for the MR8300 although it has been mentioned in the support thread for the device Flashing OpenWrt on Linksys MR8300 - partially bricked.
Do you know if I should use the current snapshot from the firmware selector or one of the instructions from the above forum thread. @cybrnook mentioned that it is now officially in master, but I don't see it.
Thanks again for any help.