Keep in mind, there is a main power plug sticking out one end, and then al the cables out the other... SFX-L is supported, but recommended against for cable clearance issues, going full ATX will only make that much much worse....?
Don't forget the Silverstone 1kW SFX-L PSU...!
The quality SFX PSUs are Platinum-rated, so worth a little bit more...? But I feel the "scalper prices" is more a supply & demand thing right now...? Not a lot of supply because of the global pandemic, but when the supply chain is back on track, pricing should return to normal...?
Most SFF is ITX & single GPU, so wattage is not a huge issue; but we have 750W Platinum SFX, rumors of a 850W Platinum SFX, and the 1kW (that's 1000W...!!!) Platinum SFX-L PSUs...
Plenty of power for the most demanding of SFF rigs...?!?
Differentiating that higher-wattage PSUs are out of stock really isn't saying anything, those are the PSUs folks want, so of course the lower-wattage units are in stock, no one needs them...!
All in all, right now is kind of a bad time to be a SFF Enthusiast, due to uncontrollable supply issues & massive demand for components...!
