I have never worn the Morelia II but I have worn other classic/heritage style boots(puma king finale, adipure III, ect) as well as speed boots(adizero's leather and synthetic). As far as the difference of how they feel just wearing them around the pitch, with speed boots I felt like I would notice how light they were on my feet and after a while they would just feel normal. When I wear a classic/heritage style boot they don't really feel heavy on my feet, they just don't feel light. Also, in no way do they feel clunky either. What you do notice is how comfortable they are and how the whole boot feels cushioned. This is particularly noticeable after taking your boots off at the end of a long practice or game. They don't hurt like they do from speed boots. They don't feel as different on your feet as you think they would. As for the upper material, a padded k-leather upper feels completely different than a synthetic upper. You still get a good, close touch on the ball but it's different. Most actually prefer the touch of leather to synthetic. I can't really explain it. The difference in touch is one thing you just have to feel for yourself. But trust me, while it might put you off at first you'll grow to love it. Hope that helps!