OK, let's just get our facts straight. Vodacom has been around for more than 12 years now, and they use their EXISTING towers which they built up over 12 years time to provide 3G/HSDPA coverage. Iburst has only been in SA for about 2 years, and they are growing rapidly! You suggest that you'll be getting faster speeds? Remember that faster speeds come at even HIGHER prices! Also, if they can't even supply the current 1.8mb/s speed to their users, do you really think they'll be able to supply more? It's not about Iburst waking up, it's about giving them time. Can you imagine where they would be if they've been around as long as Vodacom has?
I'm not sure what you are trying to say or prove there.
Firstly, let's examine the mean of "tower(s)" [aka base-station(s)] - what is a tower or base-station? - well there is usually a mast which is essentially a tall pole, and attached to each mast is radio network equipment [antennas etc], then there is a housing at the base for electrical & backup power, and usually also equipment for interfacing with one or more backhaul links...
Secondly, on just about every mast, one would find 2G|2.5G [GSM] radio transmitters & receivers that are GPRS|EDGE capable] and
separate 3.5G [HSDPA] radio transmitters & receivers. The point is that
the HSDPA equipment is newer technology and different from the GSM equipment, and was [mostly] added to existing masts [although new mast have obviously been rolled out as well].
It's not like Vodacom [or for that matter MTN] could magically transform GSM into 3G|HSDPA, these are separate networks, with different signal distribution footprints - even though Vodacom's GSM and HSDPA equipment mostly share the same physical masts or cell towers.