Quite a lot use PWM, and they do have benefits(providing your not sensitive to it). Actually more efficient and retains the same colour temp through out the modes. I have an m361n and i can not see any PWM. Now i am not super susceptible to it!!! but i can detect it pretty easy if the frequency is in my range............(what ever that it is) McGizmo and HDS iirc(just 2 name a couple) also use it, i see no PWM either way. Way i look at it, if i cant see it and it effects me in now way, i honestly dont care one bit!! It is down to the frequency and from light i have had, usually the cheaper end are the ones i spot easily................
My advice would be chill, test it out and see, if its not for you and you can detect it, then you can simply sell on here and it will be gone within the hour!............well maybe day as it is xmas
Merry Christmas