They are worth having. Now, the big question is what kind......
An old timer once told me to get a set of the box end wrenches, and the open end wrenches. Less wrenches to carry in a set, and you could use one on either side to remove something. He also said you could find them at garage sales (especially the open end ones).
I had combo's but since I wanted/liked his philosphy, I modified it. I bought Armstrong's Geared end/box end wrenches (Gearboxes weren't out at the time), and Snap-on's Open end/flare nut end wrenches. This way I am covered for a lot of the situations, I run into. I could have used the open end ones, on flare fittings, like the old timer, but after some car/plumbing work, I decided I wanted to pay more for the flare nut wrenches.
That said, I am still looking for a good deal on the straight/angled wrenches. There are times when they would have been handy, that I have used a stubby and wished I had a longer handle.
Yes they are worth it, just showing you have some options to consider.