Mattresses / sleeping pads

Based on what is readily available in SA, I would look at Thermarest. They are not the cheapest, but the performance and weight tend to be pretty good depending on the model.

I have a Thermarest ProLite 4 which I've used for several years. Excellent durability and insulation (check the R value) - 4 season mat. But yes, like every good "self-inflating" mat, it only partially inflates. You do need to blow it up a bit. This is only a problem in seriously cold climates where the moisture in your breath freezes inside the mat (not really applicable in SA).

Also check out the Thermarest NeoAir, which is fully manually-inflating (and is thus very light and non-bulky). Initially I wasn't totally impressed with it since the first generation had a low R rating which put it more or less in the same range as the old foam mats. But they have very recently released a more insulated version which has a 4-season application. Not sure if this has hit SA shelves yet. The only drawback to the NeoAir is that it is very noisy - it rustles loudly when you move on it. They need to improve on this. Test it in the store to make sure this won't bother you.

The other brands may be more affordable but watch that R value and the weight! Consider also the long-term durability (Thermarests last!). I also found that the First Ascent mats are a royal pain to roll up...compression and air expulsion is not good and its a battle. Test the rolling up in the store.

I don't find 3/4 and 1/2 lengths very comfortable, though they do save weight. And they have a limited season use obviously.

I've seen the down-filled Expeds in Canada. A pretty serious mat for cold climates! Big Agnes is another good make, but not sure if you get them here. My wife has the Insulated Air Core model, which you blow up yourself (like the NeoAir). Its pretty light and I've used it for camping in the snow.

Hope this helps.