Yes, I have. I used interstates 10 and 8. NM and AZ were unreasonably rough and debris strewn on their interstates, but it was easily enough doable. Most likely, ACA's route would conduct cyclists over a much more forgiving surface than you might find on the interstates. Not all of it through AZ is interstate. The road into Ocatillo would be the most decripit stretch of patchwork maybe you have ever seen, but again it is doable. All in all, the interstates are really not such forbidding articles for a man on a transcontinental bicycling adventure. It is also agreed that more suitable routes are available. Necessary supplies are available, though you might have to guard against getting caught in the convenience store trap. The CST is not knowing what's available at future stops, and finding yourself eating convenience store non-food for days on end till you can find something resembling a restaurant or a genuine grocery store. Yuma is OK to cycle. I have cycled through there a number of times without incident. You can go the interstate route and off the iterstate where you can or must.