PSW Dependent or Tier 2 Sponsored Visa?

[pucalee]

My situation is a bit tricky.

I currently have PSW visa which expires on 20 January 2013.
My wife has PSW visa which expires April 2014.
I want to stay in UK till my wife's visa expires.

I have two options: I can try to switch to PSW dependent (my wife as the main visa holder), but I have to go back to my country. Or, I can ask my boss at work to sponsor me for tier 2 visa, here in UK.

Which would be better to ensure my stay in UK? I don't really care about the length of my stay as long as I can stay until my wife's visa expires.

My company is a small but well-established firm, but does not have sponsorship licence. I have 3 and a half months till my PSW visa expires. Is it enough time to get a sponsorship licence? And is there any chance of not getting CoS as the number is limited? I'll be the only one employee who needs sponsorship if my company applies for the licence.

Thanks in advance.