Mark-To-Market Election

Hi, guys!
Great to join you!
Plz, comment on mark-to-market election process. Based on your OWN experience.
I googled the rest of info available.
1. How long did it take for you to get IRS Form3115F approval (provided u met all the criteria).
2. What did you choose in Part4, Q27. $50,000 de minimis election or "as needed" eligible acquisition transition election? And why? My accountant could not answer it and sugggested 50K. Which may not be sufficient by the end of the year.

Thnx a lot in advance