Not to be a devil's advocate but...
These minis will probably do better than Chainmail. Now, I love chainmail in fact I own damn-near every miniature released for it (and have many doubles and triples), but the proof is in the pudding.
How many times did I go to a store and see chainmail rotting on the shelves? Many. People bought one faction worth of stuff, then perhaps a single or two then waited for the next set. Stores had almost every miniature in its own single blister, and almost every time you would see them laying about. This is also true of some of the combo boxes, for instance a combo box that had the same stuff as the faction box wouldnt move.
So, do I think pre-painted miniatures marketed like Chainmail would do well? No. You would see high sales of certain miniatures and then a lot of old stock sitting around. They certainly wouldn't be able to have 80 initial miniatures, their first run would have to be like Chainmails - around 30-40 different miniatures. The price would be higher for big miniatures, and inevitably stock would rot. Then you release another set. Well, the old set hasn't moved, so where do you put the new set? In front of the old set. By the time a 3rd set comes out stores no longer have any space for them at all.
Now compare to their current plan. 2 different boxes, random packaging. They are able to release a lot more minis at a time, since they are random and people can't choose to not buy Female Dwarf Druid, they get her in a pack. They wouldn't otherwise be able to release such a figure as it only applies in very few situations. Additionally, when more sets come out you can reduce the amount of room you give to the core set and place the expansions in rows right next to them. It will take 2-3 expansions to use the same amount of room Chainmail (or a hypothetical Plasticmail) would take up.
This all shows that retailers are going to like stocking this stuff, especially if it sells. Additionally, whether d&d gamers like it or not, this game may draw some MtG players or other wargame players in. "Collect 'em All" is a proven business strategy, at least in the short term. One need only look to MtGs vitality to see that with good leadership the collectibe game can continue for a long long time.
Technik