Dynasty Warriors 4 vs Xtreme Legends?

[Limeface]

I picked up Xtreme Legends at a thrift shop the other day. After searching on the internet trying to figure out the difference between the 2 and getting mixed results, I figured I'd ask here.  Is Xtreme Legends an expansion to Dynasty Warriors 4 or a spin-off/sequel? Is Xtreme Legends worth keeping if I don't have the PS2 version of Dynasty Warriors 4?

[ffxik]

Think of it like an expansion.  You can play the game no problem but will get more out of it coupled with DW4.  They usually have modes and a few officers that are not in the original numbered release.  All of the Xtreme Legends games are like this.

I would just hang on to it and pick up DW4 at sometime down the road.  The game goes for next to nothing on PS2 and is fairly common.