I've been waiting for the EMIL 1951 to be available to "purchase" for 2 years now and I finally was able to get my hands on it. I knew it was going to be a case of digging so I decided to make this spreadsheet to calculate exactly where my spent money is going and if it's worth it or not. I'll try and keep this post as TLDR as possible.
Other main points is I already owned the E 75 TS, the ISU-152K, and the LT-432. I also purchased the T26E4 after 100 Gate openings to try and better my odds at getting the EMIL 1951.
All of the gold values taken for each possible item to gain are using the values as if you would purchase them either in the premium shop or in the game for gold. Decals, 3D Styles, and 2D Styles use a low ball estimate as there isn't a set price for those that is easily found.
The odds of opening a tank are exactly as the Event Page states; around 2.5% and that held true using these openings as data. You're most likely to find Premium Days, Personal Reserves, and Special Looks [ 2D Styles, Decals, etc. ] the most. Followed by Credits, Gold, Crew Books, Demount Kits, and then Tanks in that order.
Since there were 11 Key's pulled from these boxes extra, we roughly got another Engineer's starter 4% of the time.
We also only purchased the $45 bundle that contained 50 Starters and we spend $225 USD on 5 bundles of 50 Starters. We received items that totaled 209,733 worth of gold. This is a Gold per $1 value of roughly 838. This was far better than the
TL;DR from this set of data Engineer Keys are worth their weight in gold, if you are specifically wanting most of the items offered in them.
- Engineer's Starters – $1 = ~838 Gold
- Christmas 2021 Loot Boxes – $1 = ~677 Gold