So far so good. I'm missing a few camera features of Samsung's camera app like low light mode and 60fps 1080P video but other than that I like CM11 more because it's more streamlined and there's more customisation without having to install things like Xposed. Also when updating the ROM there's no need for Aroma or worrying about additional apps bundled in needing to be removed again or freezing new additions as usually found with non AOSP based ROMs.
Battery life is better, the media scanner is less harsh on the whole system but because of that apps like Quickpic which uses the Android media scanner to poll folder changes take a bit longer to update and display new images when launched.
I like the camera in other ways as it's quicker to load, take a photo and review it. It's just one seamless process and I like the Google photo app for editing, it has the best features of many 3rd party apps from Snapseed to VSCO Cam and others and is pretty mcuh a fully featured image editing package.
I like the pulldown tray more than any other stock or custom ROM. it's cleaner and better to use. I like that autobrightness levels are fully adjustable, nothing new for a CM based ROM but it's nice to have this feature back.
I've noticed a few bugs here and there. Some apps like WhatsApp crash more often and sometimes randomly forget their notification tones and revert back to System Default.
I find sound quality to be slightly less compared to Samsung ROMs though and bluetooth streaming quality to my aptX amp and car stereos aren't as rich as they are with Samsung ROMs. I guess the bluetooth stack isn't accounting for aptX or something.
A quick google shows that Bluetooth LE and aptX are missing in AOSP but are a part of Stock Samsung firmwares which makes sense given what my ears are telling me. It's not bad but it's not as good as what my ears are used to. I do hope these things make their way to AOSP.