I've used Macs for 6-7 years and I rely on them for my main hobby: music production. It was about time for me to be able to take care of them on my own. I just got a shiny new MacBook Pro and I was told that this driver kit would cover all the bases of what I would run into while working on my computer. I just used it -- along with some ifixit guides -- to upgrade my RAM, install an SSD, and replace the SuperDrive with the original HDD.
Everything went great. It was fun! Now my already-powerful computer is an absolute beast and it cost me a fraction of what it would have cost to have someone else do them.
Just do it. You might void warranties and such, but you'll save hundreds by doing these things yourself, and you never know if you'll need to do a quick repair on the fly with no time to call in for assistance.