I spent about 6 hours researching these galaxy lights last night, so thought I'd share my findings. These galaxy nebula projectors have gotten really popular in the last year and I decided that I wanted to get one too.
In the sub $100 range, there seems to pretty much be a small selection of models that are rebranded / drop-shipped / flogged off at a premium.
First, there's the Blisslights Sky Lite, like this OzBargain deal posted a few weeks ago, which seems to be the most premium in the range. However, it can only project in one colour, which happens to be blue (which many of us avoid at night-time), ruling it out as an option for me. If you would be happy with only blue, this would probably be the best option. If not, this is where this deal may help you.
After trawling through all of the different rebranded models, I came across the 'SK20' (such as here and here) as consistently getting good reviews. This happens to be the same model as the $69 Kmart one that was extremely popular and almost instantly sold out at Christmas time. Importantly, it has an RGB galaxy light and WiFi connectivity to use an app to choose the exact colour you want. From reviews, the main fault with non-WiFi RGB models is that they seem to come with a small selection of colours and disappointed those who were liking for precise control.
Looking on eBay/Amazon, the SK20 seems to be consistently around $75 within Australia, and $60+ from AliExpress, so I consider this new Kogan rebrand a good deal considering availability on the market. It is a presale with shipping beginning on the 12th January. As a result, I cannot give first hand feedback yet, rather a pseudo-meta-analysis of reviews on the market, and confidence that this is the exact same model as those. Potential negatives to be aware of are: 1) Some people talk about it emitting notable noise, potentially high pitched, while others say it's a non-issue, 2) The 'stars' project in only a green colour, which many people seem to think is a bit tacky compared to other colours (usually blue). This is a more subjective personal note, but I plan to experiment with some lighting gels to experiment with other 'star' colours.
Hope this helps someone also thinking of getting one of these! Special shoutout to the /r/tripcaves subreddit and u/winternational for posting the BlissLights deal inspiring my own research.