Hi Frankie
I think because you have been playing Shilovo, MF will feel like a next step. The biggest difference is the Theatre. MF is Eastern and T-1943 is African. This brings along with it the change of OOB's.
They are effectively the same engines, interfaces etc. Tunisia is published by a third party. I am not sure as to how many DLc's will follow. Also I am unsure as to the control the publisher has. On the other hand. Mius Front is published by Graviteam. No third party involvement. Already some good DLC's released.
What theatre interests you the most? This is probably the most important question.
You could always wait on a sale and buy them both....Whichever one you pick you will not be disappointed.
Graviteam make great sims/games and have approachable developers
Oh...I own everything they have released