I'm torn on the same decision as the OP. I've talked about it here in the past as well. I've had a VW dual-clutch in the past and did really enjoy that car, but started to miss the clutch and rowing gears... plus that was an N/A car. I think MTs make a lot of sense on N/A cars, but on modern turbo cars, the DCT is better suited since it allows you to not lose any boost during a shift. Absolutely huge speed advantage there. I'm currently driving a ~20PSI turbo I5 with a 6MT, and I wish it had a dual-clutch box on it (mostly because I fear for longevity of the stock clutch and syncros, and I'm still at stock power).
The question I've asked a few times and yet to receive an answer on though: between the 6MT and DCT, which can reliably hold additional power/torque more easily?
In VW/Audi world, the transverse DSG will hold a
crapload more torque with just a software re-flash (and then can go even further with uprated clutchpacks). Guys are putting 600+ ft·lbs of torque through the "DQ250" (which is rated for 250 N·m of torque: ~185 ft·lbs) with just a software flash to increase clamping pressures.
I can't find a lot of info on the M-DCT and how it behaves when you add power to the car... on VW stuff the transmission software flash is
necessary or else the DSG will actually send "torque reduction" messages back to the ECU and kill power gains... but in the long run, the DSG boxes reliably hold a
lot more torque than their 6MT clutches do. If BMW is the same way, and additional power is in your plans, that would be another plus for DCT...
I still think my order will end up being for 6MT though. The auto-revmatch should help alleviate some of my track day concerns (much easier to nail a downshift while braking when the car blips for you), and from the bit I've driven a BMW 6MT, it feels light-years better than my Audi. It also helps that it is $2900 cheaper in the US; I'm amazed that DCT is standard in other parts of the world... they should give you lot a discount if you take the 6MT.
