I personally moved from an astra vxr to a mk5 gti (1 month ago). Both cars have their good points, but its hard to compare them as to me they are in two different classes.
To me the golf is an 'all rounder' where as the astra is designed to be sporty and aggressive.
Everytime I drove the astra it put a smile on my face, the sound, the performance ect. Now when I drive the golf there no excitement, but there is an overall feeling of enjoyment. It's a car that doesn't need to be pushed to be content.
Overall i think the golf is a better car, better build quality, more comfortable, but to be honest that's about it. It lacks the fun factor