Malone Tune 2009 E70 First post

[Waykooljr]

I just purchased a 2009 X5 E70 with 84k.

I also have a 2009 Jetta TDI w/6speed manual trans. I did the full Malone 2.0 tuning and complete Rawtek exhaust turbo back and full delete myself. Completely transformed my car and I hit 53.2 mpg (my record) I average 48.6 at 75 mph when I drive steady without a heavy foot.

I would like to do this to my 2009 X5 35d. I have access to a full shop and auto lift. Wrenching does not scare me. I have also built three dodge cummins projects, never touched a BMW (except my 1957 BMW Isetta 300). I am contemplating a Malone stage 2 and full exhaust replacement with complete delete package.
I have a few questions for those who have gone before me...
Do I need a trans tune? Has anyone had issues from the full delete and tuning? I am getting turbo under boost code when I really get on the throttle. When I stop and turn it off and back on it goes away and it runs fine. it comes back if I really romp on it. I recently took the X5 on a 4 hour 80 mph drive @ 25.4 mpg tank to tank with no issues. The DPF light does not come on when I get the under boost code. Its a generic P0299 code

This is my first post so please be patient lol I tried searching for threads on this topic and there is a lot of threads and opinions! lol