I think 17 year old David was much more willing to take risks at both ends of the rink, even when playing against men in Extraliga. Many times it resulted in some amazing plays that portrayed him as a dominant player who confidently can deke around professionals, avoid forecheck with ease and score points. However, this risky styl often led to giveaways and odd-man rushes, where (as
Pavel Buchnevich wrote) David didn't have good enough recovery tools in terms of pivoting and acceleration to to put out the fire. Now that he's older, he calmed down in this regard and is much more selective in his decisions.
Adam usually doesn't force plays when he doesn't see the opportunity window clearly, he instead uses his skating and puck skills to buy himself more time and open up a different position.
Adam looks much more refined and in control during NT games against his peers compared to David at the same age, but I wonder if he can have the same success in Extraliga the upcoming season, where he won't be able to possess the puck as much and the opposing players will be much less forgiving. David was very good under pressure in professional hockey, partly because he didn't have the tools to escape with his skating, so he made quick, simple, yet very precise plays that most of the time went the right way for him. I think Adam will have to adjust his game a little bit in this regard.