Lumia 535 or lumia 540?

can anyone suggest me which one to buy ?

Is lumia 535 woth buying

saw some videos on youtube and it shows that there is a touch problem in the lumia 535... is the device like other lumia handsets interms pof touch and productivity, as am using lumia 620 now and quiet happy with the device apart from the apps section is the lumia 535 a worthy device in terms of the price

Want to buy a phone for long term use!

budget around 8K or less

i don't play much of games..
i need a phone which can be used for reading and social networking and messaging.
like mostly for the professional use..?

can anyone one suggest a good phone and with experience,
plus i thought of microsoft lumia 535 dual sim is that a good phone ? because OS is not a mandatory thing , i am comfortable with windows