Just because something is familiar, comfortable and that you are used to it does not mean it is great for you. For example, I have been using this mouse on my primary workstation. I like it, feels comfortable, I am used to it. However, my right hand spends a lot of time on that thing and it is actually down right horrible. It cramps my hand, the button does not always click correctly and there is only three functions (two buttons and a scroll). I broke down and bought a new mouse today. It took me a good hour to get all the functions and features right, I spend a good chunk of money on it. As it turns out, an hour of learning a new mouse and wow. I am have now sped up my usage on this PC incredibly. Basic repetitive things that I was doing repeatedly, I can now do easily and quickly with just the mouse. This one has 8 interfaces, and is incredibly fast, accurate and fits my hand perfectly. Huh. The familiar was not so good. On to the keyboard tomorrow!
Anyway, I am now really taken a hard look at things that I think are good, because they are comfortable. Reality is that comfortable things may be exactly the opposite. I suppose there is an interesting phenomena here. When things that are good for you become comfortable you are then healthy.