Let me make easy for you to decide btw GD and GS
I've bought my bike GS150 almost 2 months back and the first question,the manager asked me (Ap nay daily ka kitna distance cover kerna hai)(I said em buying for shashka purpose and like to handle heavy weight bikes)
As i've researched alot about GS150 before going to purchase so my concept was clear to get it.
Go for GS150:
1) If you can easily handle 116kg(dry) bike.
2)If you prefer power over fuel economy.
3)The bike will not disappoint you in sense of torque and acceleration.Even 3 more friends are sitting with you,It will not give you that (under-powered) feeling.(My personal experience).
4)If your daily distance is more than 40km then you will enjoy riding 150 because of no vibration and silent ride.
Now for GD110:
1)If fuel economy is your priority.(Btw koi itna khas ferk nahi hai dono ki fuel consumption mein)
2)If you cant handle heavy weight bike.
3)If you want to use for local purpose.Means local market etc.
My suggestion for GS150 uski waja yeh hai ke GD110 is overpriced.
PS:These points are my personal views.