You're on these boards, so you see all the threads with SMGII/III and DCT issues. The DSG is a very similar transmission. In the long run, the MT will cost less to fix(if you're skilled enough, you can even do a clutch job in your garage) but the DSG is going to take a professional that has been trained on those specific trannys. Plus, nothing beats a three pedal car.
2004 BMW M3 6MT - B&B TriFlow section 3|AP V2 headers|AST 4200|UUC EVO3 SSK with DSSR|ZHP knob|Orion V4|Matte Black kidney/side grills|19" VMR CSL reps|245/275 Continental ExtremeContact DW|Track stuff: 9" square style 67|275/35/18 Nitto NT01|Schroth Quick Fits|PFC 08 & 01 Pads
2014 VW GLI 6MT - APR stage 1 tune|CTS Turbo intake & 3" downpipe|ST coilovers