Yeah, I encountered it a while back and couldnt be bothered doing the crones for it back then. Since he still hasnt sold by now I figured it was okay now :P. He's only been selling for 600 for a short time afaik; his buyout was higher in earlier stages. Over that time I havent found anything to disprove of this value, though; highest offer Ive found was ~500 a.o

A seller's price can be supportive for a drop, hence I mentioned it (i.e if theres a sale at ~560 and a current seller asking for 600, then 750 is likely too high). Of course, the time it has been up is determining how supportive it is. SInce the buyout has changed a few times, its supportive value has become weaker (since the main part of the support here is that people see its available at that value and arent all over it, which would be the case if 600 was "too low"). However, the fact that you've displayed 600 as selling value indirectly still supports. Im quite sure that if you'd get 600 offered now, you'd take it.

The thing is, technically, a suggestion shouldnt affect the potential a hat has to sell. I am aware that in some cases it works that way (usually with currently overpriced hats; the only thing they have going for them is their bp price that looks high), but if a hat is really worth 750, it should be able to sell for that amount regardless of its bptf value

Tier comparisons hold very little value here for a few reasons. Main one being that all nohs apart from flies are outdated, so youd be comparing values to suggested values from long ago. Other than that, main reason nohs are so expensive is because theyre rare and 'collectible'. Many 2nd gens are rare which will positively affect their value. PE Noh is among the most common nohs, which may get them to be valued lower than otherwise lower tier effects.

In general, I try not to rely on tier comparison too much, especially not in situations as described above. I mean, blizz is twice stormy and above energies, where blizz and stormy are normally comparable. fettis and energies are similar in value. Hearts is twice ghosts. And bubbling.. need I say more. Many of these should be wrong according to tier comparisons.

Should it sell for more I can always include the new sales in the suggestion, but as for now, this should be enough for an update.