Basically you have a squat toilet like one of these:
Your basic dry squat
What you might find on a train
Many people still have them in use thoughtout the world. Some are flushable, others not.
First before you even think about going with a Western toilet (English), you'll need to find out if you are allowed to. Contact your local sanitation authority to see what is possible or required if you haven't already.
Some countries don't want people to alter their toilets as the amount of water they use can be quite high which gets into if you have enough water (arid areas), the water lines are able to support the demand and then the sewer lines able to support the extra affluent (dirty water) and lastly the processing of the sewage.
In Europe they demand a two flush system one that is light for urinating (pee) the other heaver for feces (solids). Even then these are low-flow toilets so as not to waste water and overload the sewer system.
In North America we have been lucky as many areas have lots of water, but even still there is a movement to lessen the amount of water being used with low-flow toilets as our sewer systems just can keep up with the amount of waste, and in some areas drought has also effected how we do things.
As for which is better, it's mostly a cultural issue as well as what is seen as being cleaner. If you have a flushable squat and people clean up after them selves then they are no cleaner than a western style.
Many woman prefer a western as they can keep their dresses cleaner and older people who have a hard time squatting likewise prefer the western.
Men who urinate often make a mess as the target is smaller and farther away. Even still men often mis the bigger toilet too!
One option if you are more of a squatter is to find or make a step frame like this:
Which allows you to use a western toilet in a squat position.