So far the game is running quite fine on V4. Made a 'Normal' run up to MAG weaponry + Marauder aircraft. Now just waiting for what's happening next.
Finance feels fine, most countries are 'Maxed', except Australia, which is still on 'Poor relationship'. It's simply the last country I usually cover. It's enough to finance 3 bases with a full set of soldiers without having to fight each UFO in ground combat to get even more money.
It's ok for 'Normal' difficulty, IF you know what you have to do.
Combat is fine, especially in the later stages. Terror missions are quite hard sometimes with the 'Alien Plasma Cannon', but well, that's working as designed. Harridan Snipers can be quite some pain in the ass, which is very fine too. Had one of them kill two of my soldiers in one turn. In that case it seems like smoke is not that effective.
Anyways, keep up the good work.