Bloodbath Dungeon; Thanks for the Memories

I've decided that I'm going to start the Dawn of Eradu Campaign differently than most.  This isn't a new idea, but I'm going to see how it plays out.

Characters are going to start the game with some stats, some random gear, and a physical description. HP are equal to CON and damage is 1d4.  What they don't start with is any background, description of abilities, a character class, or a single memory of what happened, who they are, or what they are. Player knowledge of the Dungeon from previous expeditions or characters can be considered part of the zeitgeist of the Bloodbath Dungeon or weird Nursery Rhyme memories coming back.  Hand-wave that shit to let play actually progress.

As these pitiful characters attempt to navigate the unrelenting dangers of the what is known to those who have escaped as Bloodbath Dungeon, they can spend their experience points to try and recover memories.  In this way the the player and the other players can start to define the character, eventually the character getting a class and memories of what happened before.

Until a character escapes, though, they will continue to wander the halls of Bloodbath Dungeon - in constant terror and with extremely limited resources.  Also, not all memories are free of consequences, many come with a price.

When a character attempts to Recover Lost Memories by Using their Recent Experiences, Roll + XP spent.

Roll + XP	Result
12+	You regain 2 memories, one as 10+, one as 7-9
10+	The GM will ask a question that you get to answer to recover a lost memory.  Gain a memory and move toward remembering more of who you are.
7 - 9	The GM will ask another player a question about your character.  This may or may not be true, you may choose to declare it accurate. If the memory is less than flattering or creates a hindrance of some sort and you accept it, that player gains 1 XP.  If the memory is negative and you declare it false, you do not gain the memory and the GM may make a move.
6-	You gain a memory, but it is a bad one. The GM will ask about something terrible with only terrible outcomes.  If you choose the memory to be true gain a memory, mark XP, and pick up a debility. If you choose the nightmare to be false, do not gain a memory and prepare for a nasty GM move.

When a character has at least 4 memories and attempts to Recover a Memory, Roll + XP Spent

Roll + XP	Result
12+	Tell the GM the class you'd like and you get it.  If it isn't available, the GM may let you look through the stack of available playbooks.  This is a very good result, so you'll get what you want.
10+	The GM will hand you 6 character playbooks and you may choose one.  If you do not like these options regain a third of the XP spent (round appropriately) or gain a new memory as 10+ above.
7 - 9	The GM will hand you 3 character playbooks and you may choose one. If you do not like these options regain gain a new memory as 7 - 9 above.
6-	The GM will hand you 1 character playbook.  If you don't want that playbook, instead gain a bad memory as 6- above.

I haven't used this in play yet, but I expect it to create a very strong reaction among the players. Those characters that survive and make it out of the Dungeon can really dig into the Dawn of Eradu campaign ... Haven is nearby and welcomes all Lost Souls.

Has anyone run something like this?  Any advice/thoughts/comments?  I think the first session of Dawn of Eradu is going to be in 3 weeks or so.  I'll make a point to update.