Personally I'd stick with GT Omega. Simlabs is very much well regarded, they were early pioneers of profile rigs bringing it mainstream. Whilst i'm sure the P1x Pro is a brilliant product in my opinion theres just nothing that the P1X Pro offers over the Prime that I can see justifies the increase in price except its aesthetics, it does look good. However, In my opinion the non standard profiles and angled uprights are going to lead to more hassle adjusting, less adaptable, and the move away from a right angled "standard" will cause issue with compatibility/configuration of aftermarket addons. Whilst it looks good, just seems to me they have prioritised form over function this time.
For example. the first thing that comes to mind is the Trakracer Keyboard tray/desk wouldnt work, nor would the GT omega one.
However if that sort of thing dosnt bother you and you like the aesthetics it could very much work for you and I'm certain its a quality product, I suspect you'll be in for a long wait though. Then again after Black Friday I'm not sure what the stock levels of the prime are like either.