The Mojo 15 has been around forever. It has recently been replaced by the Attack 16, but you can still find these under the Head / Tyrolia / 4frnt / Peak / Mojo / Fischer / Elan brands and names. It has always been kind of the underdog of the binding market. It is often overlooked for the FKS / Pivot, Jester, and STH 16. This binding performs and holds up as well as the competitors but without the high price.
The particular pair that I have has a terrible colorway that makes it look like Tyrolia took as many spare parts as they could find and put them into one hideous package. If that bothers you, you can find these in many other colorways.
If you prefer dildo style heels, these are obviously not for you. If you are a fan of the STH, then I would suggest taking a look at the Mojo. It has a slightly lover profile and is a simple binding. The heel sits on a metal track and is as basic as can be. Less shit to break while still being very durable.
There heel track is metal, as is the heel spring housing. The rest of the binding is plastic. There is probably some metal innards in the toe around the spring that is not visible, but the housing is plastic. I have never had an issue with the plastic breaking or chipping. (BTW the 17/18 din versions are the same exact construction. I have a pair of Fischer x17 and they are identical. T Hall skis on the mojo 18).
Brakes: The brakes come in a variety of strange widths (88, 97, etc) and they definitely fit TRUE to their size. It was a stretch to get the 97's on my 104 waist Heads, but they work. Here is the big downfall of this binding, and the Attack as well. The brakes are held on by the screws that go into the ski itself. If you need to replace them, you have to take screws out of the ski. That is less than desirable. You can also look at it in a positive light, they will never rip out or off the ski. I took some hard switch falls early season at Killy and snapped the end off one arm. A little bending to get it back facing the right direction and they were good to go. No plastic breaking, no brake coming completely off, no run away ski. I was very impressed and my worries about replacing were gone.
The release is very reliable if your forward pressure is set properly. I had to bump both heels up a notch last season after I was popping out on everything and from then on they have been perfect. Unfortunately there is no worm screw, they use the tab to adjust forward pressure which can be a pain in the ass. All you need is a flat head screw driver. NOTE: if you do not know what you are doing, take your skis to a shop to adjust your bindings.
I won't go into the dildo vs "tradition" style heel, as that is mostly preference of the user. These bindings are as reliable and durable as all the other great bindings out there, and for a great price.