Jeeze, it's 40 credits. If you want to the missions, do them. If you want to spend it on packs
, do that. It's called a "choice".
The game is still free. You can easily win 20 credits a week placing in the top third of DTs. There are surveys for free credits, referring of friends for free credits. Plenty of free credits.
The solo missions I've done have been fun, challenging, and unique, and once they come to iOS, I'll buy the missions.
Let's not forget while Urban Rivals is a free game to play, it's not free to run. It is part of a company that needs to make profit to continue business--to continue making countless new releases, new features, upgrades, etc.
Lastly--40 credits= $1.89. Even the cheapest DLC for console or PC based games is around $10. $1.89!!!