I bought this because I like making "different" sounds, already having several other additive synths too; I like the method you use to get the final sound which is basically setting spectral modulation/distortion from the beginning, then picking up to 10 out of 30 various modules to shape the sound - some are obvious like filters, gain, etc. but some are different although understandable such as random drops, modulator, tail; they all modify the harmonics directly. at the end are 4 effects you can dial in. One nice thing is being able to see the output harmonics for each module so you can visually get an idea of what each module is doing. The sound is good, it is additive which is to say not generally warm/analog out of the gate, but some of the presets sound different than any other synth I've heard, and it is easy to put something together fairly quickly. It's got lots of nice little perks like info boxes right on the modules, visualized circular LFO bars on the controls they modify, random button, ability to morph, lots of presets, I could go on. Suffice it to say, Loom makes additive a heck of a lot easier than the brute old fashioned way, and probably easier than several other additive synths on the market. I'm not disappointed I bought it.
One other thing that is nice is the ability to use your own wavefile as a module, which acts as sort of a vocoder using that wavefile and the parameters you can modify about how it should be processed.