I have wide, flat feet and often have to buy 1/2 to full size larger on regular shoes.  With fising boots, I have bought rubber boots up to 2 sizes larger to accomodate my feet. Standing hours on a moving deck on a fishing boat, comfort is very important otherwise it takes away from the fishing experience.  The MuckBoot Cikana fishing boots are a God send!  Comfort is obivous from the moment you put on the boots for the first time!  The soft, lined neoprene interior is very pliable and soft, width is not an issue and my feet no longer cramp up.  I have taken these boots on multiple fishing trips since I've bought a pair and will not wear anything else!  They are so comfotable that you forget you're wearing boots, which is as it should be!  The only other way to fish comfortably is to fish barefooted!
I highly recommend the MuckBoot Cikana for the most comfortable fishing boots!<a data-hook="product-link-linked" class="a-link-normal" href="/The-Original-MuckBoots-Adult-Cikana-Boot/dp/B000WH4RY6/ref=cm_cr_arp_d_rvw_txt?ie=UTF8">The Original MuckBoots Adult Cikana Boot</a>