Been on both and I found that Skelaxin didn't work as well as Soma. But doctors have found that people have become addicted to Soma so they are switching patients to less addictive muscle relaxants. Name it and I have been on it. I was on Baclofen until recently when I was switched to Robaxin. I find that the Robaxin works better so far.
You might have to experiment to find out which one works best for you.
Here is a list of others you might want to try.
Baclofen
Zanaflex
Flexaril
Elavil
Robaxin
Some Benzos like Valium and Centrax
Neurontin (while not my favorite is also one that docs give)
So if you find that Skelaxin isn't working out luckily you have many other options.
Good luck.