Scout is about 25" to the shoulder, 26" chest to bum (is that the official measurement?
), and weighs 50-54lbs. I went with the intermediate, double door, and almost 4 years and many road trips later it's still going strong. Double door has been nice for extra ventilation when I've crated her at training days or hunt tests, for visibility from the driver's seat, and for ease of cleaning.
Here she was at 14 months old in the crate, a tad smaller than she is now.
For other options you have your typical petmate, two shell plastic kennels-not as durable, but if you ever need to fly, it meets airline standards; wire crates, also not very strong and rattle annoyingly on the road; aluminum crates, strong, but $200 more at least; Dakota Kennels roto-molded plastic like Ruff Tough, similarly priced, color options, but no double door option.