I have done a lot of full contact sparring with padded sticks and no hand protection. While it maintains a certain level of realism, the participants tend to suffer from deep tissue bruises and torn fingernails (though it is better than rattan). Most of the stick and knife sparring that I do now is with minimal head and hand protection. Though I have been fond of hockey gloves, I have never been able to find a pair that worked well for stick sparring for several reasons.
(1) Most hockey gloves make it difficult to grip the stick well, especially during grappling.
(2) Most hockey gloves do not have any kind of closure system at the wrist, which leaves the wrist exposed to shots and allows the glove to come off easily during grappling.
(3) I like to switch the stick between both my right and left hands during sparring (because many people are uncomfortable against a left-handed fighter). I also use my free hand to strike and grapple, but I find it difficult to strike or grapple properly with a bulky hockey glove on. I know some right-handers who will wear a hockey glove on their right, weapon-bearing hand and a grappling glove on the left for punching and grappling. Obviously, this is problematic if you switch hands.
Because of these problems, I generally wear fairly light grappling gloves when sparring with a padded stick or knife. Although they do not offer the protection of hockey gloves, they allow me to punch and grapple well. I have tried it with rattan sticks and aluminum knives, and it can definitely be painful. That is why I am always on the lookout for a good pair of hockey or lacrosse gloves that will allow me to spar full contact that do not overly impede my ability to grip or strike.
In my school, we use a "3 shot" system during stick and knife sparring. If a fighter takes 3 total shots to the head, hand, body, or leg, he is declared incapacitated. For example, if a fighter were hit twice in his weapon hand and once in his leg (3 total hits), he would be out. This type of sparring works best if you have a referee to keep track of the shots and to determine which shots landed "clean." This type of sparring eliminates the tendency that some people have (since they are wearing helmets and gloves) to plant their feet and trade shots at one another's heads. Even with rattan sticks, you will see a fighter charge forward, get hit in the head half a dozen times as he closes the gap, and yet he will "win" the match because he is able to take his opponent down and choke him out. The 3 point system eliminates this kind of counterproductive sparring because said fighter would be out before he ever entered grappling range. The 3 point system, although not 100% realistic (though, what system of sparring can ever be 100% realistic?), is one of the better ways I have seen of conducting stick sparring.
Thanks to everyone for all of the information,
Fedaykin