Welcome!
There’s already an FAQ for smart switches versus smart bulbs. People get very passionate on both sides of this argument, but in general they each have their pluses and minuses and many people, myself included, use some of each depending on the exact use case. ( this is a clickable link)
The other people have already answered most of your other questions.
As far as the GE switches ago, they are now coming into their third generation.
The very first generation, which has since been discontinued, did not require a neutral wire at the switch but were only rated to work with incandescent bulbs, not dimmable dumb LEDs.
However, two or three years ago it became obvious that pretty much everybody wanted to be able to use LEDs. So GE/Jasco introduced a new generation which works quite well with dumb dimmable LEDs, but which does require a neutral wire at the light switch.
And there is a third-generation just coming out right now which also requires A neutral, also works very well with dumb dimmable LEDs, but now includes the “Z wave plus” network radio which is an improvement over the older Z wave generation.
So you were probably reading about the original generation of GE switches. But the newer ones will work just fine with dumb LEDs.
Smart LEDs are a different issue
All of that just had to do with dumb LEDs, however.
There is a totally separate issue which applies to all three generations of GE switches – – and any other zwave brand as well – – never have a dimmer switch which controls the current to the bulb try to control the current to a smart LED like a Phillips hue bulb.
Smart LEDs need to control the current flow for themselves. This was a big problem initially because it was hard to figure out what to do about the switch. People would understandably try to turn power off at the switch and then the bulb would not be available for other automations.
Fortunately, just in the last 15 months or so, a number of devices have come on the market which allow you to have a wall switch for smart LED’s without actually cutting the current to them from the switch. See the following FAQ:
Summary
In summary, you can use a dumb LED with pretty much any smart switch, including the GE zwave switches.
If you want to use a smart LED like a Phillips hue bulb, you will need to do something different with the switch so that the bulb always has current. See the FAQ for that.
And as soon as you mention either of these options a dozen people are going to pop up from the community telling you why one method is always better than the other, but disagreeing about what that one method is. In truth, both smart switches and smart bulbs have pluses and minuses, and you can select on a case-by-case basis as far as what you want to use. 
