if you are worried types, you can always note down the firmware you have now.
Take a screenshot of "About page" and keep it for future, which includes, baseband and other details, once done, find the OEM ROM on sam firmware site and download it and keep it.
This way you can always revert to your original firmware no matter what Rom you flash after rooting.
Use the tool by "Binary " on xda, I've rooted not less than 20 phones using it, mostly running ICS and upwards, from lava to
Samsung the tool is easy if it
supports your phone.
unrooting is as easy as of rooting.
For service center service limitations read this, I had a Tab2, hardware problem, service center in my town didn't even had its ROM, so I downloaded it, flashed it 3-4 times, but wifi problem didn't solved, then deposited it for warranty claim, it tool 20+ days for fix, but it was repaired.
What I mean to say is, Samsung Flash counter doesn't increases if you flash stock rom,
And as your phone is already out of warranty you would be delighted to flash custom roms, mods, tweaks etc etc and enjoy the phone for another year at-least and won't feel left behind with a year old phone.
Follow this to be on safer side:-
Root it
Install titanium backup from playstore, no need to purchase it works fine for backup/restore, you can pay later for advance features.
Make a full backup for user+system from "Batch Action"
keep this backup on computer.
Install mods, or change the ROM, and Do the game, beat the hell out of your phone
😛layful:
😛layful: