We at Urban Taggers do tend to consider ourselves pretty "casual" when it comes to battles. We generally don't get bogged down with anything that involves rules or planning (and therefore anything that actually requires skill whatsoever!) but regardless of how disorganised we are, we've still noticed that when playing with foam everyone will still somehow resort to some form of strategy and tactics. Whether you plant yourself on the floor, behind the couch, dual wield two blasters or use your gf as a human shield, you're still going to hide a lot, look for cover and basically attempt to not get hit. I've rarely ever seen a nerf battle where people just stand there and fire at each other without ever trying to find cover. You're trying to get the ideal shot- it's more on accuracy, less on just showering your opponent with darts.
Water fights however.. seem to be a different kettle of fish. I have no doubt there are those out there who DO organise structured, moderated wars and operate similar to Nerf battles, but as far as the casual users are concerned, I've honestly never really seen anything other than the tried and true "run and gun" tactic of shoot, run, stand around laughing until you get close enough to repeat:) One lil squirt to the head isn't going to be satisfying enough for most people; nope the idea is really to get your opponent as thoroughly drenched as possible:) This is the reason why from our perspective, screw the side arms and hand helds.. when it comes to water fighting, bigger is better. A LOT better.
With foam, the size of your blaster does not necessarily translate to it being more powerful or longer range or for all intended purposes, essentially "better". A Nitefinder will cost you around 10 bucks and probably out-perform a good number of blasters on the market as far as power, range and even mod-ability are concerned; capacity doesn't have as much to do with the blaster itself as it does with the type of ammo clip you put it with. A single shot from the barrel of a Nitefinder that finds its target will be just as effective as if it came from a Stampede or Longshot. A kill is a kill is a kill, right?
When it comes to water fights, especially casual ones, a handheld water gun will probably fire the equivalent of an 8th of a glass of water at best, but in thin stream form. If the variety of game you're playing is like assassin/street wars (and thus one of those organised/structured ones), sure that's a kill right there. But for the casual gamer, that's honestly JUST not going to cut it. In fact, it'll probably be just enough to piss your opponent off to retaliate in spades:) So while in foam, you may want a side arm, but in water fights, forget it. (the only real use for a small sidearm style blaster is for indoor "shock value" style use, like shooting the chick three seats in front of you in class)
The ammunition in Nerf wars are obviously foam darts; the ammunition in water fights is water. This means dumping a bucket of water on someone makes for a good parallel as a grenade, whereas there's nothing really of the same equal in Nerf war land (dumping a bucket of foam darts onto someone just ISN'T as fun..and forget those dumb ass Lanard scatter grenades). This in itself changes the dynamic of battles; water fights are also almost always close quarters (within 10 metres) because you just get the ranges with a water blaster as you can with foam, and you sure as hell CAN'T dump a bucket more than 10 metres away:) Water fights are also easily more likely for you to cop friendly fire, if not sheer betrayal from your team mates as it quickly spirals into a free for all, compared to a Nerf war where sides are clearly spelled out!
The weird thing is, while Nerf foam blasters are getting better over time with more power and versatility, water blasters seem to be.. well pretty much sub par to whatever was available about 10-15 years ago. Down here in Australia we've been in a drought for years and been on some pretty strict water restrictions which has definitely put a "dampener" on water fights until this past year and I thought maybe THAT explained why manufacturers had opted to not bring anything decent to our shores these past few until now.
I'm a big fan of the new 2011 Super Soaker Thunderstorm for the way it looks, but holy crap it's underpowered and totally useless in any water fight I've been in (not to mention it being electronic and hence totally useless in a pool party situation, which so many water fights are!). Water fights are also a space where the coolest looking blaster does not always translate to being the most effective- an empty Moove milk carton or a sandwich bag full of water is probably going to be very effective in turning your opponent into a drowned rat immediately than the very sexy looking, but kinda useless Super Soaker Point Break. And, unlike with Nerf (where size doesn't matter), when it comes to water blasters, you gotta admit bigger is better to accommodate the larger pressure chambers and bigger tank capacities which in turn translates to thicker, more powerful and hence wetter opponents.
I've also noticed Nerf battles tend to still be dominated by guys, whereas water fights are a lot more "girl friendly". I think this has to do with the level of complexity and rules required with Nerf wars, whereas as the free for all run and gun style play is more up the casual user, and hence female player.
I gotta admit I love the crazed anarchy of a water fight over a Nerf battle but much of this has to do with the fact that I love Summer and all the things that go with it (bikinis anyone?). At the end of the day though, whatever involves good friends and crazy fun HAS to be a good thing, whatever the ammunition of choice:)