The original Navigator or Navigator swivel with the 21 cyclones (I think the blue Walmart NV22 from the original Navigator and the green NV27 from the Navigator Swivel are my favorite ones) were probably the only ones I thought Shark got right. I don't get why those aren't still being made today while the original Navigator Lift-Away and those similar to it are however. Those are in my humble opinion WAY better machines than anything else that I've used from Shark (Though I think the Spectras from SMC I would've liked more). Even better than the one my work has, I actually hate that machine. Those are much more simpler, they filter better because of their 21 cyclone set up, they clean better, they feel more maneuverable, they seem to hold up longer, and they don't tip over while you're using the hose especially by how long the hose actually is.
But if I had to buy a Shark, as of today at least, the original Navigator Lift-Away or those similar to it is what I'd get. Preferably the white XL Professional version. I like how simple they are, they clean better, I like that it'd come with accessories that I'd find useful like the Dust-Away attachment for wood floors, the dust cup is much bigger, they've been around for over 10 years now where I'd be lucky enough to find parts for, and I remember it was one of the two Sharks that got the silver rating from the CRI.