Hello,
I have bought GS150 in August 1st week and haven't faced any issues or rust or any other major one. The drawbacks of this bike are poor rear brake (which can be marginally improved after 1st service) and poor headlight focus. The positives are its superior build and ride quality, smooth gear shifts, decent mileage of 50-55 + and good road presence. I went on a 200+ kms jorney after my 1st service and the ride quality is excellent especially in 70- 90kmph speed interval.
The rust issue was only with certain batch (mostly initial) and the suzuki guys have refunded the full amount to two guys whose bikes had severe rust.
Its a long reply but believe me you won't regret if you buy GS, for more info you can ask for GS owners in the ownership forum.

+1 to that. You can go for GS.
P.S. No CBR150, there could be a CBF150, on the lines of Stunner.
Even then GS will be more bang for the buck!

Hey GPr,

I own GS150R and Im very happy with the bike. I get 50-55 kmpl mileage. It has good comfort both for rider as well as pillion. Trust me, you will love it on highways. Its so pleasurable. No issues with my bike at least. However, I suggest you take a careful decision becos some particular lot had rust issue. Make sure you get the newest lot of it - in case u go for GS.

Test ride and decide. GS150R suits perfectly for your needs.

All the best.

How about Considering Pulsar 180 Version 4 ?Claimed Mileage is around 50kmpl.Benefits are You Will get a Bigger Engine as Well as Mileage.Just that Maintenance schedule must be followed correctly IMHO.