These are simply the most protective armor set you can find. You need to purchase the shoulders and elbows to go with this, it's just the chest/back. I chose this set after a number of friends suffered decent injuries and I was hit by a car while street riding. It really makes you think about what's covering you.
Most chest protectors are not CE approved or at best lvl 1. This set is lvl 2 all over. To achieve that it has a rubberized front to absorb energy and a heavily padded back. I ride year round and it definitely gets hot when over 90. But it also let's air through and if you are moving you'll get used to it.
I mostly ride Hard Enduro now and having this set has let me really push myself and also know I'll make it to work Monday without something broken. I've crashed, fallen and slid in these every weekend for the last year or so and they are phenomenal.