if i were u....id say id be better if u go for a raod bike.
several reasons.
1) scrams are good if got mud and sand hills...if u dun go tracking
nad got no kaki...then for what.
2) spare parts are expensive...esp if u buy KTM or GasGas...but if
ur looking for lower end....WR is the one. but even then....u still
have to think agt ur fuel consuption.
3)Dirt bikes somehow to me are a bit dangerous on road. becoz of
their tyres...s'pore roads are smooth and flat...not like JB
(heh~). if like that...where the tires going to 'makan'?? got sand
and water and oil...lagi worse sia.
gud example wud be...u ever seen a scrambler make turning like
racer??? no right? 
go for a racer....or a roadbike...i dun recommend scrams...faster,
road handling better and safer.
------------------
live hard, ride fast...but watch out for rocks. 