so how much time am i losing if i dont play with waluigi or roy?

One way to find out. Run it!

Really depends on your level - if you are at quite a low level, really not that much. If you are mid/high, it's definitely worth it to make the switch. Can't give you a number, mainly depends on your skill. Also how much time you save depends on which combo you're using at the moment.

Doesn't mean you can't get really good at the game with your current combo - just means that you will always be a little slower than someone with the same level of skill with roy/walu/dk biddy etc.

alright thanks !