Steve:
I took a look at the Dungeon Questing rules the other day. It seems like a pretty simple d6 system. Fast to learn and play which is nice. I'm not crazy about the experience bonus differences but that does hearken back to old school DND so I 'get it' from that perspective. It seems a number of the old school systems have something similar. I am interested to see how it plays without the levels and using the skills.
I think it's kewl that you can basically be and do whatever you want with regards to skills for classes. I'd imagine most folks will be a mix of skills. I noticed they streamlined the variance which I think generally makes for better overall play-ability in a system.
So far I have to say that I like the Blood & Treasure system the most. Probably because I like lots of character options, spells for casters and stuff and that ruleset seems to do well in those departments without bogging down the game with too many rules. Some may disagree but I like the balance. The PC power was scaled back a touch and the weapons and spells got streamlined a bit. Also, I do really like how they made basic magic enhancements to weapons and armor for example cheaper. The only thing that I really don't like about B&T rules is the random rolling to reload crossbow weapons. I understand the concept but I don't like the implementation. To me, it makes more sense for an untrained person rather than someone who is skilled in using the weapon. Or perhaps if the person is under a fear or other effect to cause them to not operate the weapon normally.
I've taken my Houserule Hammer to DQ and streamlined it quite a bit (3 pages of changes, mostly to character creation and advancement) adding half-elves and half-orcs, adding a faster and simpler xp system, and fixing what I consider the underpowered nature of starting human characters compared to demi-humans. I'll send out the document to everyone in a bit. I'm pleased that DQ seems to be gaining some traction on the internet. A mini fantasy campaign setting is forthcoming, as well as third-party variant rules for sci-fi and super-hero campaigns. I'd have to say that DQ is the best $2.50 rule set I've ever seen. :) Everyone seems to enjoy the skills-based characters; it really lets you design the character you want without losing the simplicity of D&D style combat and monster stats. When I eventually run DQ, I'll have my copy of Swords & Wizardry Complete at the table for access to more spells, magic items, and such.
B&T does hit the sweet spot between old-school simplicity and options-heavy new school. I like the ease that one can house rule it compared to anything from 3.0 to present. As far as crossbows, consider them house ruled to firing once every other round, as is common in most D&D editions. :)