What do you all think about the quality of the phono preamp sections built into most preamps and receivers?

Are they any good? Obviously it will depend on brand and level of the product, but I'm wondering what exactly makes up a phono preamp section.

I'm considering buying an 80's Rotel preamp/tuner and hooking it up to my preamp(that doesnt have a phono input) to use as both a tuner, and a way of feeding my record player into into it. I'm wondering about the quality of the built in phono preamp on such a component. It seems that outboard phono preamps(or Phono Equalizers, as Rotel calls them) cost quite a few dollars, some that I would much rather spend on music.