Would you invest in Manchester or London property?

Hi again

Quick question – I have raised equity through remortgaging my main residence. I have about £80-100K.

I have the option of buying two or three flats in Manchester apparently 10% lower than market price – they are rented out currently and are getting 7.5-8% yield. My thoughts are that with the £800-million being spent on the airport upgrade and the BBC moving there etc it should be a wise long-term investment………….

BUT 

I am tempted by the new fast super duper cross-rail that is coming to London in the next 4 yrs or so. I could buy a house for the same money near a station that will soon be upgraded to cross-rail in the east end, It will definitely have a positive knock-on effect with shorter commute times, improved infrastructure etc……

So what would you do? How/where would you invest that money? Anywhere else I’l overlooking?

HELP

Much appreciated in advance.

Thanks

Brian