Once again, IMO......
The DPF isn't really a flow restrictor at low RPM, so there's little to no gains to be had on the bottom end.
You can reduce "lag" and improve response time theoretically by going to Water-To-Air (a proper system, not the Mickey Mouse stuff that's been shown around here) and thus significantly reducing the charge volume between the turbo and cylinders. The OEM turbo and other "early hitting" options will quickly spool and deliver power, but will just as quickly run out of efficiency as power levels and revs climb..... that's why you see all the gains in the early powerband form fine tuning, etc. After that, you're creating heat instead of power as you're way off the turbine\compressor maps, and the electronic nannies step in to save your engine by reducing output due to EGTs and other parameters.
This is why only the exotic snail options with some sort of assist are able to do better. You need sequential snails, electric\pneumatic assist snails, etc. if you want to gain all over the place. Otherwise, you can sacrifice low end for mid\top end gains.
