I replaced a pair of Sidi Genius 5 Pros with these DMT Radials. Reason: the Radial is available with a Speedplay sole. With my Sidi's, I had to use an adapter plate, which raises the stack height quite a bit. Size-wise, the DMT Radials in size 44 are slightly larger than size 44 Sidi's. I was able to use a Superfeet insole, and thicker socks. The size 43.5 DMT was too tight. I go back and forth between the DMTs and the Sidis, and I have to say I like the fit of the DMTs better. And I have to use only one wedge under the cleat with the DMT.
Quality/fit/finish of the Sidis seems better, and I miss the ratchet buckle, but the DMTs are comfortable and much lighter than the Sidis. And they also let much more air flow thru, which is nice for those hot summer rides. I do wish they came in black....
One other thing: If I had waited another month or so, I could have purchased Sidis with a Speedplay sole. They are announcing in September.
Also: Tremendous service from Realcyclist. I ordered both size 43.5 and size 44. Sent the 43.5s back, very easy, and terrific response from Realcyclist. I'll keep buying from them due to their terrific customer service. Thanks guys.