Monoment Bass, while limited in many ways, is a beast! The presets it ships with really dont' do it justice. It's only when you start to play around with it yourself that it reveals its real strengths.
Start with the first preset and you'll see straight away some of the very clever things they have done here. e.g. Every synth I have ever owned or used has had a simple osc mixer to blend the outputs of the oscillators. Monoment has that but it also has the option to use a cross-over so that one oscillator can be your sub with the second oscillator providing all the character above it. It's such an obvious thing but still kinda brilliant. So turn that off and move the mixer all the way to Source A (Osc 1). Now go to the drop-down and start previewing those 2 gigs of sampled content to see just what's actually in there for you to exploit. It's very impressive. To make the point that it is definitely a bass synth, the samples don't go past about half-way up the 4th octave. I assume this is to save disk-space and download bandwidth.
The simplified filter envelope is an interesting thing and I think it's probably the biggest limitation of the synth. It's certainly quick and easy but it limits some of your choices. The filter itself is OK. I really like how big the difference is between the 6 dB/oct and 24 dB/oct modes. It's ostensibly a bass synth so it's low-pass only. The cutoff knob and modulation works a bit strangely. Cutoff sets the maximum amount the filter can be open and all the modulation you add uses that value as a ceiling, where every other synth I have ever used adds all the (positive) modulation to the cutoff frequency.
Elsewhere, the Punch control adds real "punch" (unsurprisingly) to the envelope attack for some hard-hitting basslines. The included effects - distortion, reverb, EQ, multiband compression and spatialisation - all contribute nicely to the polish of the final sound. There is also a kind of third osc that adds analog garbage to the patch and an Age knob that determines how much of it you hear in the output. It's not my thing so I won't say anything about it beyond the fact that it's very subtle. Overall, the sound is very good, thick and huge where it counts - in the bottom end - yet remains easy to control.
The preset browser has come in for some (largely unwarranted) criticism but what people don't seem to notice is that it doesn't just open in a new window inside your host, it opens in a new window all of its own. That means you can drag it outside your host and place it anywhere you like, like on a second monitor. That means you can scroll through presets and make tweaks as you go without having to constantly switch between preset view and your main GUI. If they got rid of the large thumbnails in the window, I reckon this browser would be awesome. As it is, it's still very usable.
There are a couple of other downsides. It doesn't respond to anything other than velocity, so you will need to program any movement or expression into it via your sequencer. 5D expression would be awesome but just a bit of mod wheel response would do. Pitch-bend does work but it's utility is minimal, at best. CPU usage is also rather high for a sample-based instrument.
Monoment Bass makes some wonderful noises and it is stupidly quick and simple to use, once you get used to it's slightly weird ways. The sound is very classy and I have a feeling it is going to feature strongly in my work from now on.