Burley London contains a slight bit of Virginia, whereas Golden Extra is pure burley.
Eh, I think you might have that backwards. I'm reading the back of the tin of Golden Extra as I type this and it states that it contains a "touch of Virginia."
To answer the OP's question. I cant compare the two as I've only tried Golden Extra. But I will say this, since buying my first tin of Golden Extra it has since become my hands down all time favorite blend of any style or brand of tobacco. It's my staple, my "stranded on a desert island" tobacco. I love burley and I just adore this blend.
As for a comparison to Prince Albert. The best way I can illustrate this... PA is like a Hershey's chocolate bar. Its a good, solid example of its kind and can be quite good. Whereas Mac Baren Golden Extra is like a fine, imported European chocolate. The both have the same characteristics, but the Golden Extra has a much better overall taste and is a bit higher quality.