Over the weekend I got it into my head to do the Class Weapon quests with all eight of my characters who were in the appropriate level range for Shadowfang Keep.

Well, actually, it was only seven, because Karelia has had the quest items sitting in her bags for some weeks now because I had her XP locked temporarily while I got more comfortable with tanking.
I queued specifically for SFK because most of these characters were high enough level already that SFK was green for them. This meant that my character was often the highest level toon in the group. Fortunately, with so many different playstyles — even the Mages are divided between Frost and Fire — I was discombobulated enough going from one run to the next that I only pulled aggro when I was really klutzy and accidentally tab-targeted a mob in the next pull down the hall (oops). Most of my groups were decent. Only two failed to complete the dungeon, and only one broke up so early into the run that I had to queue twice just to gather all the materials for the quest.
Karelia queued as a Tank; all the others queued as DPS. My tanks were mostly Paladins and a couple of Warriors. One of my groups that failed started with a Druid who was unfortunately kicked early on by other members of the group who didn’t have patience with a Bear’s lack of good aggro tools in this level range. Three of the Paladin tanks were decked out in the cloth heirlooms. The only one of them that I really boggled at, though, was the one who was also using a 2H axe and thus forfeiting the signature ability of the Prot Paladin tree, Avenger’s Shield. The healers followed the same distribution I’ve observed while Tanking with Karelia — mostly Shamans (and those mostly Goblins) and Paladins, only a few Priests and Druids.
The temptation to heal was very strong. Playing with Kaiuna, even though she’s Feral, there were times when I popped out of Cat Form to throw out some Rejuvs and Lifeblooms. Playing with Kimorene, who is Shadow, I tossed out a few PW:Shields and Renews. Playing with Kjersti, who is Elemental, I sometimes wished she could pop an Earth Shield on her tank; I didn’t do any off-healing with her, but probably only because she doesn’t have any instant cast heals. Playing with my Mages, I desperately missed the Decurse that Mages used to have at an appropriate level for SFK and now don’t get until level 30 — and sometimes very much wished I had some healing spells at my disposal. Only Kelisanna was really free of any desire to heal. And Karelia, of course, was Tanking and using Word of Glory on herself as needed.
Two or three or four is not exactly a significant sample size, but somehow it seems like the DPS that makes the most trouble for the tank at SFK level, in terms of pulling aggro, wanting to outpace the tank, talking smack in party chat, and so forth, is always a Male Orc Shaman in full heirlooms. Do adolescent male orcs take even longer to Grow Up than adolescent male humans, or this just me trying to make a pattern out of nothing?
From a sartorial perspective, the Class Weapon quest rewards are a mixed bag. Some, like the Druid and Mage staves, have identical graphics for all races and specs. Some, like the Shaman axe, are the same across specs but different between factions; the Alliance version is blue while the Horde version is red and differently detailed. The Priest staves are different for each race. The Paladin weapons have a choice of two visually identical 1H weapons for Tanking and Healing and a 2H weapon for DPS, and they are different between each race, too.
And yes, that is the DPS weapon that Karelia the Tank, who will pick up a Holy offspec when she reaches level 30, has chosen. The tanking 1H mace was not an outstanding upgrade from the one she already had, and while the healing 1H mace would have been nice for her eventual offset, both the tanking and healing weapons are exact style matches of the Might of Hakkar that can be obtained later on in Sunken Temple, whereas the DPS 2H sword is a completely unique model.
The healers followed the same distribution I’ve observed while Tanking with Karelia — mostly Shamans (and those mostly Goblins) and Paladins, only a few Priests and Druids.
This is hilariously opposite the last time I queued regularly as DPS on the higher levels (which, granted, was in late Wrath), where there were mostly priests and druids with a handful of shammies and relatively few paladins.
More recently, I couldn’t say, as my Paladins are both healers (one SFK level, one gearing for raids) and most of my other kids don’t really do dungeons, so I can’t tell what the trends are. XD