I don't think Safaricom's offering needs to compete with with Zuku quite yet, atleast on offering unlimited internet anyway, particularly because Safaricom has a much wider potential customer base than Zuku right now. It'll take Zuku quite a bit of time before they are able to boast similar coverage with Safaricom particularly because Safaricom has proven determined to upgrade their base stations to 4G and Zuku just won't be able to compete on that level.

I do think that they have to get more consumer friendly pricing but I don't think they need to go unlimited yet, it'll just burden their network without a distinct advantage to them.

I recently wrote about the opportunity that the Box represents for media here http://cdohnio.blogspot.com/2015/05/the-box-is-coming.html