Is there a difference between the Japanese and English versions of this game?

I just watched the run from joncwl on Easy mode and I noticed a few things. He can have 2 shots and multiple healing items at the same time. Whenever I play on Easy mode 1 shot is the maximum I never get any new ones if I already have one. I am playing the European version, a new game without a memory card.

Also the damage on bosses he does with the shots is way more than I can ever manage, also when they are not defending. Maybe the Japanese version is easier on easy mode? Maybe I'm missing something.

My pb was around 35 minutes a few years ago but somehow that video got lost. Maybe I'll record a better run but the record of 28 minutes is completely out of reach for the above mentioned reasons for me.

Edit: I double checked and there is no way to have 2 shots at the same time on easy in the European version. Any you can collect from barrels or by finishing stages are just not there if you still have one in your inventory. Same for other items (2 heals and 3 bombs max). There is also no very easy mode on European version at all.

So, is japanese best? I'm getting ready to start routing again. I had unrecorded runs that beat the previous wr a while back. College started up, so I never got around to recording. Starting to prepare things again.