A while ago I proposed using the Hero Engine instead of the Unreal Development Kit, but at that time the cons outweighed the pros. However, a new version of the engine has fixed many of the issues people have had, and makes the gap in power between the UDK and the Hero Engine far less.
The biggest upgrade to the HE is in the area of graphics, which is where the UDK was most superior. Here's an example:
And they will, in the near future, add more graphical features such as DirextX 11 support, which means instead of a normal map which makes a texture appear 3D, you can enable tessellation and make the material literally 3D.
They have also fixed the issues with lag. Apparently it was a result of bad optimizing in their seamless zone system. There is still some lag involved, but no more than in any normal MMO, and not in places where it would matter, like combat. And anyway, considering the way Song of the Seikilos was going to be set up, we wouldn't even USE the seamless zone system.
Let me put out the benefits again, updated:
1. It is made for MMOs. We don't need to either find a master UnrealScript coder who is willing to work for cheap just to implement a basic framework. The engine has system frameworks for pretty much everything an MMO needs, even microtransactions, but is still customizable for whatever we need. It can be used to make Farmville type games, FPS game, MMORPGs, etc. We aren't just limited to a WoW clone. Someone even made a sandbox shooter where players can build cities and such.
2. For $100 a year and 30% of profits, we get the engine and free server hosting, tech support, and server management. Customer support can cost up to $30 an hour to hire outside of this, and hosting a server can cost $15 a month. In six months the price would cover what we would be paying for a bottom-of the line server in the first place. And as for the 30% of profits, the UDK takes almost the same amount anyway... 25% of profits.
3. With the new graphics and added middleware (such as an integrated microtransaction system we can have an in-game store instead of people buying through a web site) the HE engine is just about as powerful as the UDK.
Even with its new new updates, the Hero Engine still is not
better than the UDK. But it is certainly a lot closer to being
as good. It's low maintenance, pretty flexible, runs well, and looks nice. I'm not saying we should buy a license right now... That would be stupid as we're not exactly ready to just plug assets in and build the game
But I think it would be wise to aim for using this engine instead of the UDK for Song of the Seikilos. The UDK really wasn't made for MMOs. I still think we should use it for other games, but with the new updates I believe the Hero Engine is the way we should go with Song of the Seikilos.