>it's almost like the sounds need controls that 'go to 11' to get to where you'd want them to be?
People modded the real hardware to do just that (eg. Real World Interfaces' Devil Fish mod: http://www.firstpr.com.au/rwi/dfish/ ). I'm not enough of a 303 connoisseur either to say if this softsynth is realistic or not, but maybe you're remembering the sound of modded hardware.
No, I'm pretty sure I'm thinking of RB-338, and definitely not a modded one; I had access to a 303 back in the day for a few weeks and it could have been that, but it was definitely standard. My friend I mentioned before has a number of 303s, both standard and modded, and showed me some of the extreme settings he gets on them (everything he makes is properly extreme!), but I don't know 100% that RB-338 wasn't more extreme than standard.
TB-303 was one of the synths I always drooled over as a kid, though I do think that it's legend is perhaps bigger than the synth itself was.
Going back to this Show HN: this is an awesome project. Sounds good (albeit I too can't comment on accuracy) and performs well too (ie it doesn't appear to grind my browser to a halt like many technical demos do). The UX could use a little work but frankly few DAWs have good UX in my opinion so this is at least as good as the professional products in that department.
I'm kinda the same with the 303; I have enjoyed playing with them, but never got what some others can do out of them, but I think a lot is the music you're into - I was far more into prog stuff so never really got on that well with pattern-based sequencers.
People modded the real hardware to do just that (eg. Real World Interfaces' Devil Fish mod: http://www.firstpr.com.au/rwi/dfish/ ). I'm not enough of a 303 connoisseur either to say if this softsynth is realistic or not, but maybe you're remembering the sound of modded hardware.