There has been a lot of great fights especially on their first few events. It depends on what kind of style of fighters you like and if you prefer technical fights or brawls.
I'd recommend checking out the Glory fights of Tyrone Spong, Alex Pereira, Petchpanomrung, Nieky Holzken, etc. but that's because I really liked watching them fight.
If you mean how Glory differentiates from the old K-1, it's just more modern and has more weight classes (old K-1 pretty much just had open weight and 70kg). The old K-1 had a different feel to it though and was really special especially their tournaments. The entrances and production was also more spectacular and the crowds were usually much bigger. There was also (IMO) a lot more talent in K-1 because MMA wasn't as big and the purses were also much bigger in K-1 than Glory (even though in the end a lot of fighters didn't end up getting paid).
