I know the UE3 from Unreal Tournament III, where it's doing an excellent job. Everything looks real, at least the human architecture. The aliens and their facilities is a different story.
But concerning the WW II setting I know it from MoHA where it's doing a good job. Here it's on one side lagging in collision checking, often you need to shoot enemies for "feeled" minutes. Another bad thing is the ragdoll physics. I can remember too well as I smacked an US Ranger from the church tower on the Njemegen map (Op. Market Garden) and he fell to the ground but came up the whole way again, cause is hand got stuck to some planks in the tower's floor. So he bungee jumped there for several times.
Or I bashed again an American soldier down and see what happened to him:
I'd be really glad to NOT see this in Red Orchestra HoS.
Concerning the other engines. First of all a major problem yet as Ostfront was released several players who barely managed to get RO V3.3 going on their computers had no chance to go on to Ostfront. The engine had improved that much you resulted in too few FPS and yet on the other side you could start cheating a bit. Less FPS didn't show up recoil of your weapon. You could fire out a whole drum of the PPSh without any movement of the gun. (Btw this is something that shouldn't happen again, no super broomsticks in HoS please)
Now we go for the UE3 which is still a real challenge for many computers. So we'll surely have some players here who can't join us due to a computer whose highend is reached.
If we now set out for new land on a different engine for a possible RO 3 this would kill even more.
Crysis engine is surely a nice engine but it's made for jungles and for south seas. When TWI goes for a Japan vs. USA shooter this would be an awesome engine to use. You'd have everything for jungle warefare.
Large maps, awesome water. Yet I remember the old Japanese aircraft-carrier and the old Japanese bases in Far Cry. When standing there you just need a different uniform, an Arisaka99 bolt-action-rifle and your fixed bayonet, US Marines as enemies and you feel like back in 1944.
Would be awesome, a jungle shooter with CryEngine 2 or 3 featuring a Japanese SP campaign.
But the CryEngine itself laggs in several things. Once more the ragdoll is sometimes a real mess and the collision checks are nuts on several occasions. The DirectX10 servers which have destroyable environtments are way of to be good. The blown up stuff most likely flies/falls differently on each computer, therefore you sometimes can see tanks driving against invisible walls. Simply weird.
Let's first watch how RO:HoS is doing with the UE3 and later on we can start polls for different engines
A very good thing is the 1st person body awareness. But to be honest it shouldn't be too hard to get this done with the UE3, should it?