I like to use it, but I wouldn't use it in DES at all. In CLB It's good to switch back to OP CLB and select the speed you want after the initial deceleration. Letting it reduce to green dot is asking for trouble.
I find it useful at times but honestly we can do without it. It's not prohibited by our SOP's but it is discouraged because inertia or forgetting to look at wind can catch you out. I don't think there is anything particularly wrong with the function itself, but I can understand finger trouble can cause a bunch of headache when toying with this. The above incident had nothing to do with the EXP button as a matter of fact @Winnerhofer. They took off the AP and AT when the wrong selection was made 6 miles away from the field IIRC. As far as I'm concerned that was just a messed up manual approach, which although severe can happen.
Won't be crying if they remove it completely, but it can be good fun on ferry flights.
