The obvious advantage is puncture resistance

There are several disadvantages:


weight
rolling resistance
grip
ride
cost


There are several levels of puncture resistance and a Kevlar belt is not the only means.

Let me tell you a story.  After two years on a tire with moderate puncture resistance got my first flat and had to walk it home.  I got on-line and bought THE most puncture resistant tire I could find ignoring all other factors.  It is twice as heavy as the old tire (and feels twice as heavy), noticeably more rolling resistance, less grip, terrible grip in wet, and a harsh ride.  I don't like it.  If I get zero flats in two years compared to one not worth it.

Even racing tires typically come with some puncture resistance. Some time trial tires have none.

Means of puncture resistance


Puncture resistant material such as Kevlar.
There are other materials such as Duraskin by Continental. 
The material may be only on the tread strip or include sidewall. 
Can even have a combination like a Gator Hard Shell.  
Material in tread strip
Not material specifically designed for puncture resistance - more material. 
Rubber or SmartGuard. Make the glass or thorn travel further. 
An example is the Marathon Plus HS 440.
Harder rubber
Bounce glass and thorns off and also slow them down if they do penetrate 


Pick your level of protection


Puncture resistant material in tread only
This adds puncture resistance at a very small performance impact. 
Comes in all but very very cheap tires. 
Most racing tires even have this.
Puncture resistant material(s) in tread and sidewall
Adds even more puncture resistance at still a very small performance impact. 
At this level it is more just a cost thing. 
A cheap tire is not going to have this extra material. 
An expensive tire will have better puncture resistance, performance, and ride compared to a  cheap tire.
More material (e.g. rubber)
Adds more puncture resistance but now you get into noticeable performance impacts.   
Harder rubber
Harsher ride and less traction.


Pick a tire for a combination of performance, ride, puncture resistance, and price.

What are the disadvantages of "puncture proof" (or puncture resistant) tires?
I want each individual vertex of my selection to snap to the closest unselected ones, so they superpose each other.

Im aware of the vertex snapping utility along the "closest" mode but it only work on "one" vertex, and thus will move the entire selection.

I could do it by hand but it would become tiresome with hundred of vertices.

Precision: I'd like it to work in UV editor too.

I hope I'm clear, Thank you.
