This applies to both Adsense and Sulvo so far. They all blow so far for one reason: because the top network (Adsense/Sulvo) is grabbing all of the most valuable impressions by both device type and nationality. This also seems to be why Adsense sucks when Sulvo is first and Adsense is second - because it's not getting the higher dollar impressions. Now maybe this is not entirely universal but this is what I've noticed so far. That's why people are doing well with CPA and internal ads.