I like CR-18's and have used them on both 26" wheel build ups and 700c (I think 8 to 10 wheels over the years), they tend to be durable and hold true well. I currently rock 38c Vittoria Randoneur tires on them. No mounting, dismounting issues, I wouldn't hesitate to put on a bigger tire, but Sun Rhyno Lites would work even better for something like that. I had a Panaracer hybrid tire variant on there before and had mucho trouble mounting and dismounting tires, but also had the same problem with mounting them on Mavic Open Sports. I think it is the nature of some Panaracer Tires.

Mavic Open Pro's and Open Sport's are high quality rims too, never built with them but have them on wheels that I own and they hold true well.

Anyway, I think CR-18's are a great rim at an excellent price point, a great beginner's rim too due to relatively low cost compared to the competition. That's just my $.02. I think the most important thing for rims is that they are at least double walled and have eyelets, the rest I think mostly is preference. I have noticed that wheels with Double Butted spokes as opposed to a straight single gauge tend to hold true and not stretch as much over the life of the wheel.