I don't know anything about where to download the files. I'm pretty sure this is not shareware.
I've used some IGN-maps (paper) for Algeria, 1:500.000 and 1:1.000.000 but not 1:200.000. Personally I found the 1:1.000.000 better then the 1:500.000 both when it comes to readability (colors etc) and it was also more accurate.
If I compare maps in the different scales there a lot of differences, you can find pistes on the 1:1.000.000 which you can't find on the 1:500.000, and the other way around.
It might be worth to check the different scales before you decide what to get.
This maps are old (mine are 40+ years) and things have changed since then and I guess they where not 100% correct in the first place. When it comes to important factors as water and petrol you have to calculate large margins.
It would be interesting to compare the IGN-maps with the Russian ones. The Algerian army also had some maps which I tried to buy without success.