I purchased GS-150R bike in August 2012 & completed 4000 km. The oil seal from front fork was damaged & needed to be replaced, however Show -room workshop people said the fork pipe needs to be replaced. Finally I got oilseal changed from outside experienced mechanic & no problems after that. Disc Brake was making squeaky sound upon turning of handle but showroom guys say its normal. Got that job done from outside mechanic.
Fuel economy about 50 / 55 kmpl is fine for 150 cc bike, but lacks a punch. There is always a valve cluttering sound, also mentioned by a reputed bike magazine during first ride test. Don’t know if its good for engine? Spares are an issue, don’t get them easily, service back-up even a greater problem.
Overall a good value for money bike greatly let down by poor service network, inexperienced workshop mechanics, spares issue & resale value. If going for 150 cc bike, go for Honda Unicorn instead for hassle free ownership experience, engine refinement, ride & handling & good service network.