I drove both manual and DSG ED30 before deciding I wanted DSG, I think if you drive in traffic (like most people these days) DSG is handy, stick it in D and relax your left leg, if your an enthusiastic "Driver" and want maximum control over gears and dont mind replacing your clutch regularly if you stage 2 your car then manual is the way to go
All my 7 of previous Golf GTI's were manual and this time I chose DSG as I just cant be bothered to change gear these days, plus DSG box is faster at changing than me and is lower on the Co2 if your a tree hugger
Can of worms yes, this my opinion only? very much so!.