It depends on budgets,and how far you intend to go to be honest.
The DSG is an excellent box,and allows for very fast gearchanges,especially when mapped.
The manual box is good,but not as fast,and both have good potential for coping with torque increases.
The big differences are in how far you can go before big money needs to be spent,and what the options are.
First the manual....
Stock clutch will give in quite early,at maybe Stg2 or thereabouts which is around 330lbs,and you will need at least a Sachs organic and DMF which would get you to around 400lbs,or the start of big turbo territory.
That would cost around £1k plus fitting.
If you want more than that,a Spec Stg3+ clutch will handle over 560lbs and your gearbox will break before it does.
The box itself will probably handle around 500lbs,with a rebuild and uprated bearings,if you treat it right.
The DSG....
This will require a remap to handle torque much above 380lbs,and a clutch pack rebuild for anything above 420-440lbs,and that is very costly.
