my 2 cents worth of sharing :
performance of laptop depend on the processors built in the laptop. next consideration is the after sales customer service support of the company, very important.
It all voice down what is the usage for. eg, all netbook the small version notebook, now use Intel Atom processors, this type of processors are not capable of multitasking, create, edit photos, videos, encode music, cannot run complex office software, watch HD movies. if u r doing all these, u r likely get hang or it closes all ur applications..