For expatriate Tech Services Engineers the salaries are in the range $40-45k.
Thirteenth month is not guaranteed, but in recent years only exceptional events (9-11, SARS) affected the 13th month.
The Profit share scheme policy is well defined - so is quite transparent, but obviously profit share is not guaranteed. This year it was about 16days pay - unfortunately the fuel prices took the fun out of profit share.
For expat contracts the housing allowance ceiling is currently $41,700pcm for renters and owner occupiers or $24,000 cash allowance if your rent is less than $24,000.
There is a medical scheme, but the ceilings are fairly low (e.g. $7500 per year per qualifying familiy member for GP/Physio).
The medical scheme DOES NOT cover any maternity/childbirth expenses, however the public hospital system is of a higher standard than the UK NHS, and is becoming the preferred option for expatriates.