I have been using T310 since last 1.5 years, and found it really wonderful.
I bought it for 9000.00.
The pros:
Tri-band
Color
Cute size and looks like male phone
Joy-stick is wonderful and the menu navigation is best among all the phones, just 2 clicks and u r in the menu which u want to be in.
Voice recorder
Polyphonic ring tones
Battery life is real good as against to that of other phones from SE.
IR
fast dial
Computer connectivity via cable or IR
Rugged: even it felt a couple of times, nothing happend.
Reception is real good. Even when Nokia fails to get signals from same service provider, my phone works.
Absolutely no problem with any SIM be it BSNL/Airtel/idea/Hutch...
Cons:
Hardware gives problems, and I have changed motherboard, keypad and screen:-) so everything, But after changing its without any problems...so it may be a problem with a particular piece.
memory available is not good enough for bigger images/many ring tones
Recorded voice can not be used as ring tone
Cool gudget overall....