Do you eventually get anything special from the "Special Battle" in the Battle square of the Golden Saucer? Ive tried it around 5 times now and i've received different items after each battle. Being about Dio, and his battle history etc. Do I ever get to do anything other than fight the same monsters over and over again in the special battle or am i wasting my time?

Aren't you suppose to get the Final Attack Materia?

Not sure if that's the right place, but I think you get W-Summon along with Omnislash. It's been a looong time since I played, but I think that's the place.

you can get lots of stuff once you get lots of points

if you beat the special battle the first time without dying you get the Final Attack Materia. I think. It's been a while...