@Ken_R makes a good point on the gap-based binding vs "kiss" gap bindings. Although it isn't necessarily a "new" binding vs "old" thing as there are many new bindings coming out with heel gaps (Mtn, ATK varieties, etc) as well as some now 5+ year old bindings with kiss gaps (Ion, Vipec).
Some new intriguing kiss gaps bindings are the the Marker Alpinist and the Fristchi Xenic. Both of which are <300g bindings.
No one is going to be able to tell you fine differences between the TX and the MTN unless they've skied them both. The way all those design characteristics come together into how a ski skis is more than just the sum of its parts. The MTN is most likely a good bit damper simply due to its size.
Some new intriguing kiss gaps bindings are the the Marker Alpinist and the Fristchi Xenic. Both of which are <300g bindings.
No one is going to be able to tell you fine differences between the TX and the MTN unless they've skied them both. The way all those design characteristics come together into how a ski skis is more than just the sum of its parts. The MTN is most likely a good bit damper simply due to its size.