I'm playing
this redesign of Super Metroid. Shit is SO cash. It really feels like I'm playing a SNES sequel to Super Metroid -- only, you know, with all the same bosses. But still, from what I've seen so far (3 hours and 2 bosses in) the level design is top notch, and the modified physics and enemy strength also add some novelty value. It's definitely more challenging than the original, although not nearly as hard as
Super Metroid Impossible. The fastest tool-assisted speedrun I've seen clocks in at just over an hour, so I assume it's roughly twice as long as the original Super Metroid.
For what it's worth, I tend to think most rom hacks/game redesigns are complete shit, so this isn't just nostalgia talking.
There are some full runs on YouTube if you want a peek:
[youtube=560,345]AvRscM8-fSY[/youtube]
Anyway, if you're interested then get the patch here:
http://drewseph.zophar.net/