I do it just to get tethering. Everyone saying a JB is too buggy...well you installed something that caused it. Jailbreaking doesnt mean you go to cydia and install every tweak/add-on there and expect the phone to run correctly.
i agree but then why jailbreak?
It could be some SBSetttings bug, or activator, or many other simple things.
My iPhone 4 worked fine when i first jailbroke it was fine, then the screen was shutting off in the middle of me using my phone as well as the home button would not work.
The same thing happen to my wive's phone, screen shutting off and home button not working even thou we had different tweaks.
In MY personal experience, the bugs outdo the conveniences of jailbreaking.