Because of the difference in thickness, will the comp ratio rise much with the thinner metal gasket? Or does the standard EA gasket compress down to a simmilar thickness anyway?

I havnt had to change the headgasket yet since putting the turbo on, but expect to soon...a metal gasket is what I would opt to use but I dont want to raise the compression

well yes it will increase the compression ration but by how much i have no idea cant be too huge
ir might gor form 8.5:1 to 8.6 to 1