I had a chance to ski in a pair of the new Apex MC X boots recently at the Stratton Mountain Trade Show. I am a strong, expert recreational skier and normally ski in Lange RS 130 boots. My boots are performance oriented; stiff and have a precise and technical fit. They fit so perfectly, that I must use the thinnest socks possible. If I use a regular ski sock, I will cramp up, but, with the thin sock, I am absolutely comfortable all day long. The boots are an extension of my leg and feet and transmit energy very efficiently to my skis.
With that said, I was skeptical that the Apex boot, which is so comfortable, warm and easy to get on, could deliver enough performance to make me happy. I figured the trade-off in control would be huge. The sole length, (because Apex boots are really a snowboard boot with a removable frame), is about 16mm longer than a traditional boot. Therefore, theoretically, your leverage on the ski should be compromised. However, the reality is that, although there is a loss of some crispness (I wouldn't race using these boots), that loss is surprisingly minimal. I felt in total control and was able to feel the skis respond as I leveraged them from the balls of my feet. When I skied the boot, I didn't have my custom insoles, which would have made the performance even better.
My conclusion was this: For those people who put a high priority on comfort; warmth and convenience, and perhaps have had some trouble over the years with all or some of these considerations, the Apex boots could be the answer. They are warmer than a traditional boot with a $200+ heating system; they are extremely comfortable and very easy to get on and off. In addition, the frame can be removed to allow it to be as comfortable as an after ski boot for walking around or hanging out.