I searched and While PE is not a fan of blix here is something he wrote:
"There is no connection between archival quality and the use of blix or bleach-fix. The argument is removal of silver from color films which affects grain, sharpness and color repronduction. In E6 films, it can also affect whites."
"With a blix, there is a chance to have silver retention with some film / blix combinations. This is due to the heavy silver load, the type of silver developed, and certain inhibitors used in color films to control image quality. The dyes also act to protect the silver from the bleach and so the dye cloud must be rendered penetrable by the blix.
There are ways to limit any problems with blix kits.
Use a long blix time! Use 2x – 4x the suggested time or more. It will not hurt. It does make the process longer.
Mix the two parts right before use and in the quantity you are going to use. Don’t re-use it. But, this increases cost."
The link to the full thread titled "Just how bad is blix vs bleach & fixer?" is here.
Also of interest is the post "The definitive word (I hope) on color stabilzers! " by PE