I found all Sophos Network Access Control features valuable, but IP blocking is the most useful.
Sophos Network Access Control requires a lot of resources to work, which is an area for improvement. The primary concern is that it has a lot of agents running as it's an endpoint solution, so when you apply the solution on a 4 GB system, you'd need to upgrade to an 8 GB system. At times, you'd even need to upgrade to 16 GB so the agents can run confidently without impacting your operations.
I understand that one of the reasons why Sophos Network Access Control uses up more resources is because of all the patches added over time. Still, I wonder what will happen in the next four years. It could mean that you'd need to buy a 16 GB system to ensure that Sophos Network Access Control runs very well, so Sophos needs to work on this area to ensure that the system uses up fewer resources when agents run.
The Sophos Network Access Control pricing also has room for improvement, but I know there's not much you can do about it. Sophos recently had a fifty percent off promo, but here in Nigeria, there have been some FX issues, so if you pay $10, for example, years back, that could be the maximum price, so about ten thousand Nairas. That no longer applies today because Nigeria's FX issues have affected Sophos products' pricing significantly.
If you're buying Sophos Network Access Control here in Nigeria, you have to pay based on the black market exchange rate and not on the interbank exchange rate, so you can't even blame the channel partners who earn that way. I'm unsure if Sophos can work on the pricing because many users find Sophos Network Access Control very expensive. Two customers who have used it for one year stopped using the product and decided to try Norton because Sophos Network Access Control is very expensive.