Vapor,I have the EVO and 901. I find myself reaching for my 901 with the passthrough any day where theres a usb plug available. I have the TW 901 and i have read here in the forums that some people are having a better experience with them than other 901's, like better reliability. For me i cannot say because the only 901 i own is from TW. Oh and my TW 901 atomizer has lasted me a month of heavy use now.
I too own the TW 901, Its great, but its just not what im looking for in an out and about e-cig. Its great at home though i must admit. Im really thinking about the m-401 and the titan from TW.
Is the 401 reliable and does it give that extra hit to your throat?