There's a bit more variety in the liquid cans than the DME. At my LHBS, the only DME choices I have are Extra Light, Light, Amber, Dark, Wheat, and Pilsen Light, pretty much all by Briess. In the liquid section, you've got countless choices, by Brewferm, Brewer's Best, Cooper's, Alexander's, et al. And the liquid cans will be dialed in to reproduce a certain style, rather than just color like the DMEs.
One thing to remember is that any kit, either DME or LME, is always going to be made better by steeping specialty malts or doing a mini-mash. According to Ray Daniels in "Designing Great Beers", while you can make actual award-winning beers composed of 100% fresh extract, it's much easier to create a tasty, award-winning beer when the extract is more like 25-67% of the fermentables.
Dry Malt Extract will store longer than the cans; LME cans will eventually get darker and darker, and the hop oils in any hopped malt extract will turn metallic-tasting. I've not seen a hopped DME before, so you're always going to be adding your own hops to the recipe; many of the LME kits will be pre-hopped, which makes it difficult to adjust the hoppiness since you might not know precisely what IBUs the finished recipe is sitting at. You also don't want to boil hopped LME.
One thing that my best extract-brewing friends recommend is that you should always use the lightest extract available (e.g., Alexander's Pale Malt LME), and then supplement that with steeped specialty malts to adjust the color.