UK General VIsitor VISA - Trip Duration??

[mjain100]

Hi Friends,
I am living in UK on Tier 2 ICT VISA. My mother is planning to come to UK on General Visitor VISA for 3 months.
Shall I make application mentioning duration as 3 months or just , lest say, 2 weeks becasue VISA will be granted for 6 months anyways??
She is able to show funds equivalent to 2000 pounds in her Indian account and properties worth equivalent 5000 pound(as ties with India). Why am I having this doubt is for reason that longer the duration can trigger more strict checks and they might not consider 2000 GBP balance as enough funds or they might reject on the basis that 3 months trip is not required for general leisure visit.
But I do not know showing duration lesser than intended is good idea.
Any suggestion will be very helpful.
Thanks in advance

-MJ