Unfortunately the forum restricts us in the features, but we've added a forumwhere you can discuss online retailers. You can vote and post your experience (as detailed as possible).
The forum is moderated, so only staff members can make a new thread (read: start one about a company) and all threads will be using the same template. (See example)
This thread can be used to request stores for which we should make an indiviual thread. As soon as you've made a request, a moderator will look if it's not a duplicate and create it.