I have just started to migrate from Lightroom to Luminar. At the moment it means using Apple Photos as my catalogue and Luminar as an external editor.
Luminar has a few rought edges which I think Skylum is addressing. For example, I find it a little laggy at times, it actually crashed twice during the first couple of hours of experimentaion. There also seems to be an issue with the apparent sharpness of files during processing. With regard to sharpness, I found it best to apply sharpening in Photos itself after processing in Luminar.
The Luminar user experience is very different to Lightroom and I’m taking a while to acclimatise. However, I have hight hopes that I will be able to develop a streamlined workflow.
The main reason I moved to the new software is the subscription model that Adobe has established. Call me a luddite, but, where possible, I prefer the standalone software option; especially at a third of the price (Luminar is currently on sale on the app store).