Yeah I prefer the always there slider. Much better than the double tap. Of course not everyone will like it. Perhaps Apple might make it an option to change in settings.
Nice addition for sure, quick access to the camera button is very important.
Double tapping was slower, cumbersome, needlessly wore out your button more and it was out of the way so you'd forget that you can open the camera from the lockscreen.
I like it a lot, but I wish you could change the default camera. I prefer Camera+ to the native camera app, so it would be nice if I had direct access to that, instead. Either way, the camera unlock is convenient to have.
I wish Camera+ could be a default as well. I'll probably just use the iPhone camera for those quick pics and edit them through Camera+ if needed. If I really need to use the stabilization or multi-focus feature, I'll unlock and use the Camera+.
I can definitely see the trade-off of a quick picture from the lock screen winning out over unlocking and opening Camera+.