Questions before I purchase.

I am about to purchase the MPVI2 with Pro-Features and a PCM Modification for my 2015 Challenger 5.7L. I am totally new to tuning (As in I know nothing about it but plan to learn) and I have researched DiabloSport and HP Tuners. HP Tuners has way more options and customization from my understanding which is great. My questions are:
1) Will I be able to get the car dyno tuned at a shop and later modify that tune if needed? I know HPT seems to have a certain file type they use and wasn't sure if that would cause issues.
2) What are credits? I've read up a bit on them and not quite sure I still understand them. Will I need to buy them every time I wish to edit my tune or dyno tune?
3) If I choose to can I have a tune emailed to me from HemiFever and use that? (HemiFever was just an example I'm not sure if they are DS only or not.)
4) Last but not least does anyone have any tips/tricks or advice I should know before I dive head first into this?

I appreciate any and all help. Thank you.

1. If you buy HP Tuners, a shop that does dyno tuning can just use your interface to flash the tune in. This way you wouldn't have any issues with them using theirs and not allowing you to alter "YOUR" tune without spending more money.

2. Credits are a one time cost, each vehicle/computer costs a certain amount. I don't know off hand what a 2015 Challenger runs for credits but it's surely on the website. You buy the credits and license your file/computer, that's it. You can make unlimited amount of changes to your file after that for no cost.

3. Lets use HemiFever as that example. If they also had a HP Tuenrs MPVI2 device, you could email them your stock tune, they could change that file for you and send it back to you, then you could flash that in. Any file that isn't yours to begin with would cost you money and you could risk hurting the computer if something didn't match up.

4. I'm not a dodge guy, so I can't help with that. Reading and more reading is the best thing for learning that platform. Maybe there are classes or books/guides out there for Dodge tuning but I'm not sure exactly.

Thank you so much for the information! Definitely helped make my decision. Sounds to me like if I get any tune that's not my own, the safest way to do it would be a dyno tune if I am understanding correctly. I will continue to research and learn as I save but I am definitely purchasing HP Tuners. Thank you again 5FDP.