I would appreciate it if someone can explain the difference between persona+folder redirection and without regarding network traffic.
as you pointed it out, there is really no difference in principal, the difference will come into place depending on the environment. is there shaping going on the network? where are the shares being serve from? what type of user and their work? these questions might make the deployment shift from one practice to the other.
but one should think about why folder redirection was implement, and that was to help out with profile corruption because of size (slow login/log off side effect, profiles should be as small as possible), sure persona enhance help profiles further, but I don't think these enhance are meant to replace folder redirection, but rather compliment.
in my deployment I use all the tools i can get my hands on, quotas, file screening, roaming profiles, folder redirection, and personal enhance, it might be more work, as a result I don't have to deal with angry users with slow login/log off (something you will definitely experience if you don't use folder redirection) - and profile corruption.
good luck
Sam