We arrived in Kruger during the Cricket weekend and entered at Malelane Gate to Skukuza for the first night.
Then spent one night in LS, Satara, Letaba and two at Maroela.
Traveling on secondary roads was no problem.
I think it would be wise to stay off roads that do not allow caravans.
For us the biggest problem was the heat at that time, I will do this again but would choose a cooler time.
If you are not lucky enough to find good shady spot to stop during the heat of the day the Motor Home becomes an oven.
Even though it does have an aircon, it does not help a lot.
The late afternoons and evenings were great though. (The aircon was great during the night.)
Arriving at a camp and setting yourself up is a pleasure, you find your spot, make sure you are parked level, plug in the electricity cord, take out the table and chairs and pour something cold and watch the other campers sweating whilst setting up tents.
Some things to remember is to stop at the shop if you have to buy something before finding your camping site.
If you do go for a late afternoon drive, leave you table and chairs out so that no one takes your spot, same if you stay more than one night in a camp.
Remember to open the gas bottle before you start you day's journey if you want to use the stove during the day at a spot where you can not alight from the vehicle.
We never used the toilet inside the camper, purely because we did not want to empty and clean it but it was a comfort to know we could if we had to. (SO is a bit squeamish
But it is nice to have the basin available.
We had a 5 sleeper although it was only two of us and it gives you lots of space to move around and for packing.
Make sure you pack bottles etc. carefully as they can fall over and break or leak easily.
I (as the non-driver) enjoyed the freedom of moving to the back, relax on the bed or make coffee during the drive.
Your SO will enjoy reading and being comfortable.
Check everything properly on receiving the vehicle as one of the back windows of our van did not open and it was a bit of a problem.
If you like camping, don't mind driving most of the day and don't want the hassle of packing and unpacking every day this is the way to go.
Cost wise it is about the same as a guest cottage or bungalow.
Hope this helps.