Have had no issues or regrets at all, I just wish I had done it sooner if I am honest.
MPG - Better
Performance/Responsive - WAY Better
DPF - Gone, so no worries of an expensive repair
Smoke - Never Noticed any real difference (But I do have to clean up my tail pipes a bit more as they are a bit sootier these days, but its a quick wipe)
I am still really impressed