I have never tried a 901 atomizer, but I would have to think of all the variables, resistance must account for at least 90% of the differences. But your comment makes me wonder how the coil placement is different. I got some SLB 510 atomizers, which have pretty much the same resistance as the 901 atomizer, and the difference between the SLB atomizers and my regular 510 atomizers was like how people describe the experience of using a 901 atomizer.Big difference in TH and flavour between the two models. Resistance is only one variable in the equation. 510 has better TH but less flavour than the 901. Because of coil placement and barrel length, the vapor from the 510 is hotter when it gets to the mouth also.
. I hate them. I wish they'd change them back.