I just called Collectormania...no other major events besides a standard Magic tournament (of course) on the 19th, so we're good to go for two 4x6 tables that day. I'll be there at 1100.
@Dakkar, regarding the April, May, and June dates...I always plan these for Collectormania, trying to stick with the "same Sunday, same location" mantra to make it easier for people to plan. Collectormania is also a good midway point for the Denver and Springs gamers. And to be honest, it's just easier to get tables at Collectormania on the weekend.
I love the Haven, it's a great store, but they are so busy now that they have scheduled game days every day of the week. While I've not yet had a problem getting one table on a Sunday for something Spartan, I feel that I've just been lucky....all it takes is some new historical gaming release, or for all the historical gamers to show up, and we won't get even one table, let alone two. That's nothing against the historical gamers--Sunday is Historicals at the Haven. And that's nothing against the Haven either--they are so popular that they have to "direct traffic", so to speak. Not a bad problem for them to have, but it also kind of shoehorns players into playing their game only on that game's allotted day/night, and it's impossible to predict when everyone who plays that system will show up. The staff is pretty good about accommodating people who are playing a game that is different than what is scheduled for that day, but if all the tables fill up with games that are already scheduled for that day, there isn't much they can do. Which, again, is understandable.
But it all adds up to making it unpredictable, and Collectormania is more predictable.
All that being said...if you wanted to put on a tournament at the Haven, that would be a little different from our monthly meet-ups, I think. At least it is in my mind. And it would be better to hold a tournament at a store that supports the game--Collectormania is happy to give us space, but they don't carry any Spartan products, nor do their distributors (as far as I know). The Haven does.
All just my $0.02, of course. And I'm certainly not the one in charge.