if you want a good phone you'll need to spend the $$$.
You are comparing a $200 phone to a $600 one. try getting a htc one, or a lg g3 or the new moto x for a change...
I had a Moto X. It wasn't much of an upgrade over my Nexus 5. Definitely not worth the price increase.
regardless, the nexus 5 might have its shortcomings but lag is not one of them. i wonder what "customisations" you put in place to render it unstable.
I've tried everything. Stock android (4.2-L), Cyanogen, PA, Pac Man, AOKP, Stock + root, stock + exposed framework and gravity box. Android just is not as smooth. I see frames drop, overall lag, unresponsive touch, apps crash, animations taking forever to start, and random quirks all over the OS such as lock screen doesn't display the right song when playing music from the Google Music App, keyboard (stock, kii, swiftkey, fleksy) still staying up even when I go to the home screen and am no longer in a text field, youtube videos stop playing whenever apps update, etc. Android has so many quirks and just feels extremely unpolished.
Granted, I haven't used iOS since iOS 6 on my 4S before I got my Nexus 4. But from my experience, iOS 6 was smoother on old hardware than any of my Nexus devices running the latest OS.
in any event, to each his own. my whole family uses iphones and i prefer android.
Yes, everyone has their own preferences. To be fair, I am not sure iOS 8 is my preference. I haven't used it, didn't have much experience with iOS 7. I could use it when I get my iPhone and absolutely hate it and go back to Android. But right now I do not expect that will happen.
what i just find comical is how apple tries to sell people the idea of a "revolutionary" product when it uses technology that has been around for a while. whether it actually runs smoother, integrates better or what not is another story.
This year something hit me, Apple doesn't really try and sell hardware. This year more than any other they really pushed how well the software and hardware works together. And from what I've seen and heard, it seems they are right. With Android, the hardware and software never go as well together as on an Apple device.