I have been working with propeller for a year now, I buy push traffic on the promoting offerers (mostly tier1).

Platform is very user friendly especially for viewing statistics and optimizing the campaigns, the only thing that could be added is the possibility to upload the creatives in one load instead of one by one.

Quality of traffic is always on high level and volumes are quite stable. If you have a big volume of traffic then you will have a personal account manager and all questions are resolved very quickly.