no, the V1 mini’s are still good. They are just a bit out of scale compared to the larger V2’s.
As far as what booster packs to buy? IMO you should start w/ some North Africa and Eastern Front Boosters if you are into mid war. Buy Early war for…you guessed it, early war period(not my fav). If you can manage to find boosters from Base Set I, Base Set II, Contested Skies or D-Day you will want to pick those up if they are priced reasonably. They can be pretty much impossible to find at an affordable rate. ebay is a good place for singles, try to buy inexpensive lots w/ a diverse amount of common/uncommons from different sets as you will want multiples of these anyway. Counter Offensive is the latest booster and is in stock pretty much anywhere online. Extra maps can be tricky to find, I have resorted to making my own terrain instead(pictured). Hope that helps!
