honestly, the more time you put into it the better you'll do. It can just help you and not hurt. When are you planning on taking the exam because 25 hours isn't much really. Unless youre really crunched for time, Id take them all. Why base it on what others say as opposed to seeing it for yourself.
How about this, skip the PAT and RC for all of them.
And when it comes down to the QR, time yourself to finish in only 30 mins. Obviously you won't finish QR, but it will give you good practice of choosing your battles.
I took them all except the final I just did the orgo + gen chem + bio.
I think taking tests and finding questions you miss is a key element to your studies. You need to learn to study more efficently and really key in on your weak areas.
I'd take them all since you have them, take a test then the next day study what you miss. Rinse and repeat your way to victory.