Hard to beat Kitchen Worktop for affordable suitability. It's about the right depth, fairly hard-wearing, and is oil, solvent and water resistant. Might even be free from a skip! Available in several colours – I go for plain white because it makes the stuff I do easier to see. Others might prefer dark.
What may matter more is what's underneath. Thought it takes plenty of weight when properly supported kitchen worktop won't bridge wide gaps without bending.
Mine has a slight lip at the front which is both annoying and useful. The lip stops small parts rolling off, but I can't lay big stuff flat on it.
Some people like a sheet metal top, and Bill's hardboard suggestion is good for temporary work. David George mentions an oiled hardboard top that's changed every year. Yes!
Always worth asking what the worktop is for. Beyond the obvious that a proper woodworking bench is unsuitable for clockmaking, and vice-versa, what's your goal? My workshop is entirely utilitarian. It's a mess, full of inexpensive tools that get used. Though I clear the decks for safety reasons and when space is needed, and tools are kept where they should be, I don't care what my workshop looks like. To me tools are disposable; provided they do what I want, that's good enough. Others enjoy tidy, clean, workshops and expensive heirloom tools. Some worry about who makes the best spanners in the world and keep them in glittering professional-grade tool cabinets. In an extreme case, the hobby consists of pottering in a wonderful workshop without actually using it.
Nothing wrong with people indulging themselves however they please – it's a hobby. My point is, choosing a worktop might be more to do with individual opinion rather than raw practicality. The second-hand kitchen worktop that suits me could be utterly hateful to my best mate. I might think he's daft spending good money on solid beech, but it's none of my business. We're dancing to different tunes.
What's the reason for asking? If your kitchen worktop failed for practical reasons, it should be possible to suggest alternatives. Other suggestions if the reason for wanting to upgrade is cosmetic. Either way it's likely the alternatives will more expensive than kitchen worktop…
Dave