Either Zong hates me, or their performance wildly varies (4G).
When you perform a speedtest and no aggregation is present, forget about getting decent speeds unless you're lucky. On weaker signals, it's even worse - it's as fast as edge, but since latenices are much better on 4G, basic data services work. With aggregation present, its much better.
Mobilink, on the other hand, works well without aggregation in most places, and even better with (it just makes it a bit more resilient but doesn't necessarily give you more speeds). I don't know if Zong have their towers connected via fiber but I remember someone from Mobilink saying most of their towers are connected via fiber (and microwave in some areas).
But the thing is that even in weaker spots, Mobilink performs WAY better than Zong, even without aggregation in MOST places. No contest. except in places where there's a ton of concrete and Zong have a tower above your head. But then, Mobilink don't have 4G coverage in every urban place either, and their 3G signals are jammed in some places.
But I wonder why Zong behaves so poorly vs. Jazz with the same signal strength in most places.