FWIW, there are very nice Tektros and there are crappy tektros. A few years back, "Bicycling" magazine would dis any bike with Tektro brakes in their reviews. Or, more accurately, they would dis the brakes on any bike that came equipped with Tektros.... I guess they hadn't sprung for any ads.

If your Tektros are, in fact, turds, you can totally swap them with ease. Just make sure you get the proper reach, and that they'll mount up with your bike (I'm guessing they're short-reach 39-49mm, with recessed mounting nuts...but measure/investigate before you order anything.)

As for recommendations for the replacements: I'd get pretty much anything Shimano, or nicer Tektros. I've never been able to forgive Campy for having single-pivot brakes, but some ppl can tune them just fine,