You don't have to view Harrison Mixbus as a start to end DAW to produce in. There is always that partial ground where Mixbus can be used.
The trick to it is to use your DAW as you normally do and go right to the end in terms of your mix. But instead of summing everything in your current DAW export a series of stereo stems. You should be able to represent even the most complex mix with a handful of stereo stems and a few individual tracks.
The trick is to import those things into Mixbus and just do the final polishing and summing there instead. Their plugins are great as is their reverb too. But most of all is the sound. It does have this sweet Harrison type sound to it.
The three EQ's on the tracks, buses and the masterbuss are all
different. The tape saturation is very controlled. I am not a big fan yet of the dynamics processors but that may only need more time to get to know them better.
I started actually mastering full stereo premastered tracks too making it easier to get to grips with. Their mastering processors are very good indeed. Once you get that down then you can start bringing more into it and getting it to do more as time goes on.
It will be a long time yet before it will have all the features required to do a complete audio/midi session on it with all effects. But in the mode I am suggesting it actually rocks bigtime, now.