Bajaj Discover 100T vs Discover 125T vs Discover 125ST - comparison

Hi friends,
I am looking to buy a new bike and I have short listed Discover bike but there are again 3 good variants I found in Bajaj Discover series ie. Bajaj Discover 100T vs Discover 125T vs Discover 125ST, now I am very confused and I need help. If anyone can guide me and give some comparison of these bikes. I want bike which should be not very costly but have good mileage as well as decent looks and that is the reason I short-listed discover series.

Looking foward for guidance and help from fellow members of the community.