Yes its true, I also have Ud100 since year 2011, its a bit underpowered as compare to it's heavy body weight. usually touch 80km max (can go up in some cases) . Also Body parts are hard to find in local market [Karachi], my mudguard and assembly got damaged and was not able to fine good quality parts for it in gulshan or akber road. All other parts like engine etc are compatible with 70 model that's a good point at least.
But Don't buy it if you are looking for some speed competing machine
& yes its also true that this bike is very comfortable, will you believe that since the purchase of this bike, I have not started the bike with KICK. only used start button and hear you go , parts quality is much better as compare to local chinese bikes.
Good bike with quality parts and comfort & great sporty look.