Hi John, at present we are flying 4.101 stock until the final version comes out for UP 3. You can install UP3 over 4.101 and use the switcher for co-ops. UP3 is on RC2 at the moment and it should be able to update to the final when thats released There are a LOT of good things in UP3 like 6 dof, loads of new maps and flyables. See the MODS part of the forum for a video of the new Tunisia map. It looks stunning