I have very wide feet, ~294mm long and ~118mm wide when I trace my foot and measure. My toes are a bit on the short side so the ball of my foot is relatively far "forward" which means most of my foot would fit a size 13/13.5 better but short toes would leave a lot of room at the end. I also have a very high instep and very high arch, narrow heel.

My current shoes are an older pair of Sidi Ergo Mega circa 2008. They have stretched nicely and fit my feet very comfortably. My vague recollection is that they were a bit snug when new but I went with them because of sponsorship at the time. The heel is loose a loose fit. Durability has been outstanding! I recently replaced the top straps and the velcro just separated from the vinyl strap portion. Impressive durability.


Current comparison search:

1) Trek RSL size 45.5: I need to try a size 46. A bit tight to put my foot into them, they require at least one hand, probably both hands, to put them on because it is designed like a sock instead of a shoe with a tongue. The top Boa has a well designed strap which prevented the wires from creating pressure points during my brief fitting. Heel cup is a nice size for me. A little bit of pressure on the little toe side but that is likely because of the shoe being a half size (or more?) too small. Definitely not as wide as the widest of the Lake shoes but very stretchy upper would likely accommodate my foot in the correct size. Fairly noticeable upward curve of the sole at the toes. Feels light weight. Very nice design and quality look shoe. Wearing the shoe while editing this post and it already feels more comfortable on my foot. The end of the toe box has a rubber-like "bumper guard" which is forcing my toes inward a bit and might be an issue long-term in this smaller size- or not. With my short toes it means my foot is wider then normal where the toe box typically begins to narrow. With longer toes the shape would probably be fine. The lower (toe) Boa wire don't create pressure points either. This is a really well designed shoe.

2) Lake CX333 Wide, size 46. A wee bit too short. I measured my foot at 293mm and a 46 is supposed to fit 293mm. Width was slightly too narrow compared to the comfort of my stretched out Sidis but much wider then the Trek RSL. Also not quite as wide as the CX242 Wide. Material was ugly on the white ones, looked like wrinkly plastic film that could tear easily. Probably wouldn't, but that was the appearance. A little concerned about pressure from the top Boa wires across the top of my foot because the tongue seems to be very thin, especially compared to the old Sidi which is a wide strap and well padded tongue. The same shoe in black must be made from different material (I think black is leather) as it looked much nicer/more durable. Again, may just be appearance of durability. Race Last is ~114mm wide in size 46.

3) Lake CX242 Wide, size 46. See #2 re size. I ordered a 46.5 to try. The material seems better but may just be appearance. Shoe seems to be much better ventilated- MUCH better. Not that the other looked hot, this just has a lot of mesh to it, like the Trek RSR to some degree. Width was noticeably wider then the CX333 and was very close in comfort to the old Sidis. I wouldn't hesitate to wear these, new, for a long ride once I have the right length. Competition Last is 118mm wide in size 46.

4) Sidi Ergo 5 Mega: According to Sidi the Mega width only adds 4mm. I'm guessing it was the same in the older version? The buckle system is unfortunate on these shoes. I like to snug them up before a sprint, nice and tight, then release the pressure. That seems, from what I have seen and read, to not be "easy" compared to the Boa system or the older Sidi lift-to-ratchet buckle. That old buckle was a bit on the sucky side with full finger gloves. New one looks worse in that situation. If they had gone with Boa or something other then what they have I would consider trying them on.

Lake size chart for reference. I wish all manufacturers could be so informative.
lakecycling.com/pages/sizing-chart