Just fresh from installing the HDMI kit for the Dreamcast, the same group releases another kit, this time for the PS2 Slim. I already have a Retro Gem installed in my personal PS2, but I am certainly going to put aside a console and give one of these a whirl. Only thing I can see just from my brief glance at the product page on Ali is it does not have 5.1 audio, which does not worry me but maybe might be enough for some people to give it a pass. Still, $80AUD compared to over $300AUD for the Retro gem once you factor in shipping it will be interesting to see how it performs. It won't be as feature rich of course, but I honestly have not used many of the features available on the Retro Gem, so this may be a very good alternative for those that don't want to spend the money or are on a budget.
Get one yourself here: https://www.aliexpress.com/item/1005008512226576.html