I say that they are great for a novice who is just trying to make sense of this instrument, but once you hit a certain point they really tend to hold you back. The reasons I prefer notation to tabs are many…here are a couple: Tabs tell you one specific place on the fretboard to play a lick or chord, but in reality there are tons of ways to play that same exact lick or chord somewhere else on the neck. This may not seem like a big deal to some, but each of us has our own unique style and they way our hands lay on the fretboard varies from person to person. The way BB King might play a lick may be totally different than the way I would naturally play the same set of notes, and if reading from tab I might be forced to play one way or the other, whereas notation gives you the freedom to choose where to play a set of notes. Of course, this requires the ability to read notation, but once you can read it, a whole world of theory opens up to you and it’s only then that you can truly appreciate how endless music is. I suggest that you try to learn to read music, it will only broaden your skill set and help you to think logically and abstractly on the guitar.
One thing that’s really good to practice is every day when you pick up your guitar try sight-reading something relatively simple, like a single line melody for violin or trumpet or something without chords. You can probably pick up some used sheet music for these type of instruments from a garage sale or used music shop (usually really cheap too!) Spend the first 15 minutes of every practice day reading through these without stopping if you make a mistake. The key is to force yourself to keep going along with the metronome, and you’ll suddenly find yourself much more comfortable reading notation, even so much so that it becomes just as easy or even easier than tabs.