Beside training in a gym we train also in different environments.
We have outdoor classes where you feel completely different. Small change like noise of the street, cold, darkness creates scenario. You need to use other senses like hearing, touch. It is very unlikely that you will be attacked in your gym. In real life you could be attacked in a pub, dark alley or car park. Sometimes can be cold, sometimes can be hot and sometimes can rain all day and you need to go to work, shopping or meet your friends. In our training we try to train in different environment as often as we can specially to get used to uncomfortable situation where we are not control the circumstances.
Another thing which make krav maga so good is that we do not spend a time for doing something which is not practical. We have no forms like "kata" we try to avoid fancy kicks which on the street or in the pub is hard to use.
In self defence most important is to defend fast and efficient not just look good.
Krav Maga is very practical system. We use environment to help us survive. Anything you can find around you you can use in self defence (stones, sticks, chairs, etc.) obviously accordingly to the situation.
I could write lot of things why Krav maga is so good but last thing I want to mention is 3-rd party protection or VIP protection. Not many martial arts if any has built into the system how to protect others not only himself or herself.
I hope this short article help you to choose smart.