My old saddle was very comfortable, even after long rides.

However when I first got it, it was only mostly-comfortable. On very flat rides it tended to get unpleasant after a while. I actually thought about looking for a new one. Then the guy at the LBS adjusted my seat height and position, and that made it perfect.

Now it's all worn out, and I'm using one that's okay but not great. I need to keep searching.

As for saddle width, if you read the various threads about sit bones and saddles, especially responses from Knotted Yet, you'll see that the recommendation is for a saddle that is wider than your outside measurement, to give you a centimeter or so on each side for shifting around while riding.