My buddy is in the exact same boat as you.. His mk4 is costing him as much to repair as it would to get a low end mk5 at this stage so he actually wants to buy mine!
I personally prefer manual which is what I went for because unless you know the history of the servicing of the DSG and the previous owner(s) were enthusiasts it could cost you a small fortune! Tell tale sign is hesitation when pulling in low gear... Get a current DSG GTI owner to test your future car. They'll know if it feels different!
Rust in Ireland is not an issue... UK uses much more salt on the roads so the wheel arches rust. It's really not a big deal, enough fighting with VW and they'll look after some of the cost. Early models also suffer boot badge rust, again a cheap replacement and finally the diamond cut alloys will develop white worm eventually but you can either re surface or spray paint!
When you eventually find the exact car you want, post the link on here and ask for advice then get a current GTI owner to come with you and if they have a VCDS cable to scan the car it's even better!
