Is a metronome really worth it?

Ive been playing guitar for 9.5 years and have just recently (little over a year) been focusing on technique and stuff. Before I have always jsut played and played and not worried about anything else. I am always hearing peopel talking about metronomes and I cant figure out whats so good about them. Even advanced players use them and i dont know whats so great about it. Cant you keep the rythm yourself, or am I missign something. Basically, should I get a metronome and WHY?
Thanks in advance

You can keep the rhymn yourself but you can use a metronome to see how fast you can play/practice scales. Or if you wanted to play a song the exact tempo as on the recording. I dont use a metronome but those are some reasons why you would use one.

Ametronome will keep you on a perfect beat ie. 100 BPM. Whilie a human won't be perfect ie 76.467 BPM. Using a metronome will help your timing. Just a fact. Timing is essential in creating great music.

Yep it's definitely worth it. You might want to look into a basic drum machine instead though considering the prices. A decent drum beat will help you keep track of where your downbeat is and you can program alternate styles like swing or shuffle beats.

I think a met/drum machine is nigh on essential for improving speed and accuracy...and timing...you dont have to have one in order to play well...but your skills willl develop much faster and you'll be (I cant promise...but it should be true) a better musician for having used one.

the answer is YES.....only if you want to be very accurate and good ;) .

Certainly it is worth it. As a beginner, you'll more than likely notice how off time you are. it's helped me tremendously... just start slow and as you progress, start turning it up.

I downloaded a program called leaf Drums and I use it as a metronome for practicing, you can come up with your own beats and tempos. It's pretty darn cool.