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I installed 12.04 on an ancient Toshiba laptop several years ago, and it worked quite well. One of my acquaintances recommended that I upgrade to 14.04. This I did, but only with great difficulty, and this installation has been very buggy the entire time I've used it. Recently it failed entirely and eventually I gave up on trying to fix it and reinstalled 12.04, which works just fine.
I realize that this is an obsolete installation and will reach its end of life in April, but since it works for me, is there any compelling reason that I should try upgrading again?