Android App Performance

I've been doing a little bit of research and I'm stuck on which engine would be the best to purchase for developing android applications. I've narrowed the engines down to construct, gamesalad or stencyl.

My question is how good is performance when developing for a android device? Will it be better than the other engines I have listed?

Also on a side note, is there any plans to add the ability to make Windows Phone 8 applications?

Thank you

From what I can tell, C2 appears to do Windows 8 phone apps already, and for the time being, potentially better than Android apps.

Don't quote me on that though. I have a feeling something good may be in-store for us regarding Android soon, but again, not sure.

My finished game runs quite poorly on Android atm, so I'm waiting for either CocoonJS (wrapper) to be updated, or something official from Scirra.

Why not use PhoneGap?