Most definitely, I don't see why not since it seems as if you are stuggling with M1 and it will help you with your chosen uni course. I found M2 to be significantly harder than M1. S1 on the other hand is quite easy, but relatively long. The hardest part in S1 is the normal distribution, so watch out for that.
Not so much that I am struggling, finding it pretty easy actually (since I am retaking, hate retaking though), but, from what I know, most uni courses prefer stats over mechanics for the course I want to do.
I got onto biomed with the same subjects with statistics 1&2 and some of the skills you learn in statistics actually do come in handy in the lab work you do on that degree course. A lot of the crazy maths comes into it too. Stats is also supposed to be easier yeah, so I'd say go for it