[eluser]Ergose[/eluser]
So far the project I'm finally starting to wrap up (Domain problems set me back some time while we got my system working right again.) is doing quite well using the CI framework. Now, I chose to use the MVC parts of CI for getting an admin backend going quicker, but the front end is less MVC oriented, actually it's just CV and get's the job done. Depending on the application I could see where it would get sticky, and I have found some unexpected quirks, but I've tried Zend and others and there are tradeoffs across the board. I went to CI because it was the closest to a MVC type setup that was fine with PHP5, didn't package scripts out the wazu with it, and the modules are loosely coupled as far as I can tell. They also tend to organize everything how I would if I had built something like this from the ground up (which is originally what I was starting with when I found CI, and was like wahoo!)
As for resources and such, if your app is getting hit so hard that it becomes an issue, then you should probably outsource the hosting anyway, or update the systems. Besides, at the level I'm estimating would be required for there to be really serious problems, I'd be less concerned about the framework and more concerned as to why I didn't hire a team of developers to build a more customized inhouse solution/framework months before it was even an issue.
Just my take... but that was just off the top of my head. Hope it makes sense. Sidenote though, it would be nice for CI to come with a model building script for database access. I like making a model for every table to help with CRUD functionality. It's nice, but does take a little effort. I found a great tutorial on making the models, and modified them slightly, maybe I'll post them eventually when I settle on some stuff.
