Unless you are really after the RGB squircle, the Thermalright TL-C12C-S triple pack for $15 or so would be a way better buy. According to Hardware Canuck's testing, those outperform the Arctic P12 ARGB.
Not sure about the P12 being beat by a TL-C12 unless its compromising on performance elsewhere (noise levels/rpm/etc). Can you share the link? Also the C12s come in a bunch of variants, using different fan blades or possibly different tech-make-up. I was looking for a particular C12 flat type ring but couldn't see one.
I don't usually bother with fans with curved/bending outer rings around the blade. I've always taken the position that flat rings circling the blades effectively push more air opposed to curved rings which IMO add turbulence or fall short of static pressure up-keep. Maybe this is one of the reasons why fans like the Montech AX120 and TL-C12 (both curved) tend to perform less effectively with radiators/dust filters.
The P12 (the absolute budget daddy-of-em-all) sticks to a flat ring - i guess directing airflow more efficiently without curvature leakage or bounce-back turbulence.
I'm certainly no curvature expert, although i do love curvy curves, just not on me fans
Any thoughts on the above?
EDIT: should have mentioned, the above thoughts are based on non-RGB variants.