Standard Arabic is the basic , once you learn it you will figure out that you can speak with anyone from middle east . 
By the way , you make me laugh . 

I hope to be traveling through Sudan and Egypt one day and want to talk to people. To get me able to talk to people in both of these countries quickest, I´m curious to know whether people more knowledgable than I think would it be most efficient to learn Egyptian arabic and Sudanese arabic (not bother too much delving into standard arabic), just one of the two, standard arabic or would it be nesseary to learn all three? 

Actually, as students of English, we face this kind of problem; the gap between standard and colloquial. It's much easier for us to understand the standard variety, like news language, than the colloquial one.

Ha, this was great. Really though, the disparity between the Arabic "dialects" is far greater than, say, the difference between Urdu and Hindi (which are linguistically, though not officially, the same language) , of course the different varieties of Arabic are considered one language due to history, religion, politics.. Etc (the same reasons for which Urdu and Hindi are considered separate!) But really, most of my non-maghrebi Arabic speaking friends cannot understand a Moroccan Arabic speaker unless they've had exposure to MA. Whereas in English "dialects" are all pretty much mutually intelligible (barring some obscure Scottish varieties). Like the comic suggests too, Chinese has a similar phenomenon, there are many many distinct varieties that are barely (if at all) mutually intelligible. Still they all share the same script.However, "official" or"standard" Chinese actually resembles a spoken variety (like in English) whereas standard Arabic is not the first language of anyone (in the modern era!)

Made me laugh from identification. I love it! :)