Yes, my iPod and iPad are jailbroken and it's great. You just need to know what you're installing. The only reason my phone isn't is because I have 2 years of Apple care.
I am the master at Jailbreaking. Yes you should. It will not harm your phone at all TRUST ME I have jailbroken my iPad and it is amazing. it is not a virus. So yay. The only problem is, if you have 8.2 or 8.3 you can't jailbreak because i0nic is being a noob and not releasing his jailbreak to the public. I think either TaiG or Pangu displayed a work-in progress jailbreak that is said to be coming out on June 30th! hopefully. They tested it in MSS (Mobile Security Summit) and it has a few minor issues and 1 major issue that they will fix. So do it once the new jailbreak software comes out. I love the jailbreak! Sadly apple patches things that can be downloaded with no jailbreak needed that are not in the app store like nds4ios, gba4ios, snes4ios, etc. it really dissapoints me on how that is happening!
I don't advise it. I jailbroke my iPad + it was good for almost 2 years, then my entire iPad just broke down and i had to delete everything off it which made me really sad. I had over 3 years of pictures on it. :/
I heard jailbreak on iPhone and immediately thought of this: After some research, I figured out what it was though. xD
Jailbreaking is where you install a software that enhances what you do on your phone basically. You can get extra things that favour you in a certain aspect.