Don't own one - have fired several, including one owned by my cousin.
They're cheap, come with a lifetime warranty, are relatively accurate, and the ones I've shot cycled pretty well with no jams.
On the other hand, they're awkward both in feel and in looks, they're heavy, bulky, and they have a limited service life due to the construction materials (expect them to start falling apart after a few thousand rounds - though with the lifetime warranty, as long as they remain in business, Hi Point will replace a shot-out gun for free). My cousin's also managed to snap the magazine spring in two after a while. He just bought a new mag for it.
Personally, if I were on a very, very limited budget and really wanted a gun, then I'd be ok with one - though I'd still probably try to find a better used gun instead. If you can afford to save just a little bit more though, the S&W Sigmas or Ruger P-series are a much better value. On the used market, look at the CZ-82. It shoots the 9mm Makarov cartridge which is a bit hard to find sometimes, but otherwise it's a very capable and VERY well-built handgun (my only complaint for mine is that for it's size it's a bit heavy, though that isn't really an issue when the alternative is a Hi Point). Alternatively you can also find PA-63's (also shoots 9mm Makarov) for probably the same price as the Hi Point.
I think they ARE in a different class than the Jennings type pistols though. The Jennings are a gun for suckers that is more like a paper weight than a real "gun". The Hi Point is at a similar price point but is still designed and made by people who are trying to make a product that actually works, just with enough design shortcuts to keep the price down. You have to expect some drawbacks from those shortcuts.
Truthfully, I'd like to see Hi Point make an actual sleeker locked-breech gun with a steel slide and see what they could do in more like the $250 price range rather than the $150 price point they're at now.