Yeah, there are the perks that it is usually more body-safe than water or oil-based lubes because there's no glycerin or paraben or, in the case of some flavored lubes, aspartame or sweeteners.
Another perk is that it lasts longer during sex as a little bit goes a long way. You don't have to use very much as it spreads a lot and stays wet. It's also easy to wash out of fabric (or at least the ones I have used are.) They're also generally condom-friendly.
The downsides in my experience have been that they aren't safe to ingest, even in small bits, so you won't find them in any flavors and they aren't good for oral sex. They are more expensive (but higher quality) and they are not good to use with silicone toys as the friction of silicone on silicone can cause the toy to crumble.
My fiance and I like to use flavored or water-based lubes for oral and toy fun, but for penetrative sex we stick with silicone.