Hi nikonian guys out there..wanted to ask some opinion..im planning to buy a dslr..n i would prefer nikon..coz i used to play my brother's d7000..so im a bit familiar wit nikon UI..budget is limited..is it worth to get d5100 which doesnt hve built in motor?is it a good investment for about next 2 years?or i just buy 2nd hand d90 which have motor inside..is the motor is really a problem?

I c.thanks a lot yah..