I've used iPhones since the iPhone 4 launch to the iPhone 6 Plus.
I usually ended up jailbreaking them in order to unlock their true potential. Apples sandboxing sure does throttle them. On the flip side this is why they are considered more secure than Android. I'm not 100% convinced.
It's a breath of fresh air with my s7 edge. The customisation is off the chart coming from an iPhone. Mines unbranded with no network bloat ware.
The joy of being able to place an App Icon on my home screen where I want and not where Apple dictates is a joy.
As for iOS updates. Yes they are typically better at pushing them out, but as Apple wants to drive the newest out on as many different iPhone models they can this can have an impact on the phones health.
On my previous iPhone 6 Plus I ended up having to throttle its aesthetic features to stop lag because of the most recent iOS update at the time.
The s7 edge screen is just breathtaking.
Some have issues being caught up in Apples Eco-System. Not in my case !