I sadly wore Sidis for almost 9 years, because that seemed to be the brand to buy, and they are one of the few companies that make women's shoes in small sizes. I had to wear 2 sizes up, but my feet always hurt.
I now have Shimano shoes, both road and mountain. I love the wide toe box. Even the slightest change in thickness of socks (I have several types of wool cycling socks) make my feet ache, and this has been mitigated a lot. The road shoes had the molding process, which was OK, but the inner liner that came with the shoe strangled my foot. The LBS told me to wear the shoes without the liner until they figured out what to do. I went to the Good Feet store and bought a pair of ultra thin liners like the Sidis had and that was that. Perfect. The mountain shoes also had a problem with some nails poking up through the sole, but DH and the shop woman mechanic figured it out. I like these shoes even more. This is good, because I will be wearing them on our trip to the San Juan Islands.
Nothing ever comes easy for me, but once I had the initial issues solved, I love my shoes.