Pros:
-Its a BlackBerry. If you are professional/ self-employed, it is a must. Impression matters. If you believe in "first impression is the last impression" thing, Q10 is better than iPhone.
-Solid build. Feels premium once in hand. Build quality is at par with Nokia.
-The OS, BB10 feels different and premium.
-You do not have to buy a BB plan to activate BBM or such thing. A simple Rs. 100/- p.m. 3G plan giving you ~300MBs will work.
-Yet to test 3g, but it gives almost 2 days backup if on 2G.
Cons(painful ones):
-BB makes a fool out of you.
-It is good for Rs. 25K at max.
-Cr#$py camera.
-If you are ok with not impressing your client, this phone is a crap.
-Maps simply do not work. It shows you a blue dot on a white background and thats it. No maps.
-Many minor software glitches, like you can not copy paste sentence/word in many apps.
-Too few apps in App world. for eg. it doesn’t have TrueCaller for BB10. There is a True Caller app for BB7 but not for BB10.
-On a scale of 100 if user-friendliness and convenience are considered, Android and iOs are 90+, Windows and BB10 are below 40.