I have been using Bajaj Discocer 135 DTSI from more than 2 years.
I have not encountered any issue till now. I drove more than 10000KM including some long trip i.e. 400 KM in a day. It worked great with comfort. The best thing I like about it is its mileage. I easily get 55-60 KM/L on city and 60-65 on highway.
Only problem is when we go more than 95 KMPH the engine vibrated much. The look, pickup and handling are also very good. I think bajaj should also provide engine switch off button as available on pulsar. In Discover we have to use ignition key to switch off the engine.
Over all I am satisfied with this vehicle.