Files must be handled one at a time; cannot be handled en masse. Cannot copy filters and then alter them - each navigation filter must be done individually. Cannot clone products and then update. Each must be handled individually. Application tends to run quite slowly for us. Some expected functionality falls very short, such as blogging. We had to do a lot of custom code to create category pages, archive widgets, etc.
Initial implementation fell largely to our team, rather than the vendor. Rather than deliver a finished product, we were expected to create all content and navigation (we were moving an existing site into the platform). For small sites, this may not be an impediment, but for a large site, it is more difficult.
You cannot migrate staging updates to production (content & product changes). Everything must be replicated by hand in the live environment. This causes a lot of duplicated efforts, especially for larger updates.
It is difficult to do customization on the fly - almost all customization must be done by either highly technical house resources or vendor resources at additional cost. We are rapidly outgrowing the inherent functionality.
Built-in search engine is quite limited.
The UI is pretty buggy as well.
I wouldn't recommend iAPPS if you have a large highly customized catalog, or if you want to manage your customer database outside of iAPPS. It is est used as a complete solution for small business with limited product catalogs. If a great deal of your content strategy relies on blog functionality, I wouldn't recommend, as set up requires vendor development and is unintuitive.
There also seems to be a high level of attrition, which makes me wonder about the work environment.
Upgrading from a home-grown system that required IT intervention for almost all changes was really helpful for our marketing group. The ability to manage metadata on a page by page basis (including CSS &JS as well as SEO metadata) has been tremendously helpful for us, resulting in an increase in our organic SERPs translating to increased revenue.