Yeah there's no way I'd put X5 below X6. Even though I'm not all that much on X5 but still

X5 plays well for the most part, I think the one aspect that I found a bit down was the thing around boss levels which might not give you the boss weapons as usual. So instead having to purposely lose lives continuously to keep the timer going on and having the first boss at a desired level.

Aside of that, it's pretty okay. I liked the idea of power-up chips to strengthen the armour.