The following documents can help deciding whether to upgrade to UnO or not:
Here are the free downloads of the UnO firmware binary images (no registration required). Two binaries are available: one for 32Kx8 EPROMs, one for 64Kx8 EPROMs.
Please follow these 
firmware upgrade instructions to perform the upgrade.
UnO Firmware v1.0.2f for 32Kx8 EPROMs (type 27C256)- UnO Firmware v1.0.2f for 64Kx8 EPROMs (type 27C512)
If you don't know how to handle these binary files, you might prefer to 
order a ready-made EPROM instead. Ordering a chip from me is also considered a sign of appreciation for the long nights I spent implementing the feature requests gathered from the FCB1010 community.
After upgrading to UnO, the User Guide mentioned above is a must-read. If you decide to do all the programming on the unit itself (without any kind of PC editor), you might find it helpful to have following chart at hand: