Icarus3

The good:

• 3 x Oscillators which you can create some rather cool stuff with.
• 3 x LFOs.
• 1 x Step LFO (user customisable).
• 2 x MSEGs.
• Resynthesis (very cool, bit hit and miss though).
• Vocoder.
• 2 x Filters (chained).
• Wavetable editor.
• Half decent preset browser.
• Arp editor.
• Drums editor.
• Glitch editor.
• 1 x Vol Env.
• 3 x AHDSR Env.
• Wavetable paradise (almost).
• Lots of effects (but there's more to this).

Overall its not that complicated to use, and you can get some great result just keeping things light with OSC1 to 3 and playing with the LFOs, MSEGs, Arp and/or the Glitch machine.

The bad:

• Step LFO module should be part of the main editor area as it's user editable, so its a very small area to edit what you want and often is a trial and error repeating the note for a very very long time till you get what you want. Also no presets.
• Routing, LFOs are fixed into modules and divided between OSC1 to 3 & Filter 1 & 2. So you get only 2 LFOs for OSC 1 to 3 and 1 LFO for the filters. You can however drag LFO 1 & 2 to other things resulting in some insanity (but this can be a good thing), but overall this is a limiting design/approach to things. It ties you down, bitwig will help you greatly here. Same with the MSEGs but Bitwig can't help you with that as they don't have a MSEG modulator and doubt we will see one for many years yet.
• Preset browser (everything starts with 3 stars) where as it should be zero, and you can't give a zero star rating.
• Presets are stored in with the VST folder (should be in the documents folder as per most other synths).
• Preset classification, what is a seq or an arp is often in the leads or bass folders and so on, even worse for the expansions, they are all over the place and you have no idea what you will get next, best to ignore the folder names and due to this a drag and drop and create folders feature would be good so you could re-organise or delete but there's none of that.
• Expansions / Additional presets, very poor, 25% of them if that are any good, very poor sound design.
• The effects are often overpowering, their presets are drowned in them and are often unusable for anything other than showing you what they can do. Reverb ducking is nice though, every reverb should offer this but I pref to take my effects out to other 3rd party vst's I've purchased but some are very usable. So use them gently.

Overall, you can make some cool stuff but don't rely on the presets or the expansion presets, the good ones in the factory presets is as good as it gets, making your own is where its at. If your a preset junkie, this is not for you, if your into sound design you should enjoy this VST but you will soon find yourself wishing it did things in different ways and needing more LFOs and you will get annoyed with that step LFO. Those with bitwig will get a lot better use out this VST thanks to its modules (modulators) which can be assigned to nearly everything inside the VST giving you superior control than what the VST offers alone.

Worth a buy?
If you have Rapid or Avenger, NO.

If you want resynthesis and don't have Halion6 or Falcon, maybe, expensive for just that though.

I would say its a YES, if its on sale (50%+ off), you have Bitwig and enjoy sound design, but don't waste your money on any of the expansions, maybe grab the wavetable expansion only, and then set a good few hours aside to make some cool sounds ranging from the usual to the insane.

As for this becoming part of someones daily / weekly workflow, I don't think that will happen, well not for me, I might reach for it now and again but I will probably only end up using it when I have something unique I think it will be good for or I have started to accumulate a lot of presets I've created, which will take much time.