In general, I've been very happy with Afrihost. I have seldom had reason to contact technical support, but I have noted that their response time and the quality of their responses (general technical knowledge of support staff, etc.) have deteriorated recently.
Afrihost I rate as 'Good' because the fibre link is sometimes slow and there is never any notification as to potential issues. They have all my details so if they are aware that Vumatel in an area is down or slow, they can surely send me an SMS / WhatsApp / email. That would be taking their service to 'Excellent' in my book. Their pricing is not the best around but is close enough for me not to jump ship. With LTE perhaps becoming more affordable once bandwidth is made available, fibre may lose customers unless prices drop.