What is the best set up to test traffic?
Experience teaches best test is with $120 budget across 3 days.
You should set up your campaign with $40 a day (approx 40.000 imps a day), with a bid at recommended level as indicated here for desktop or here for mobile, and let it run for 3 days.
Then you have sufficient volume to see what works or not, and what need to be adjusted.
Of course, you should setup the tracking correctly, so you can monitor live what sources are profitable and which must be blocked by our autoblacklister.