@Kulchaz: What throuputs are you getting with Orange?
@AllanK: HSPA+ 21Mbps is what Safaricom has on 3G, not to mention their 4G trial. To get 21Mbps for any operator, all network conditions MUST be perfect (which is a sheer impossibility) and the user must be the ONLY user in that cell at that time (which is a rare occurance). That is why you will never get 21Mbps on 3G mobile broadband - on any network, anywhere in the world. In 4G, you may because the maximum theoretical throughputs are quite higher.
The laudable is more often than not rendered laughable by overclaim