Not at all. I know a ton of people who mix and match brands. I did originally (my United's got recalled though, so now I'm using Ride for both board and bindings).
The only time you would really have to worry about it is if you ended up with something like EST (Butron uses). You have to get burton bindings if you use a Burton board that has EST.*
Regarding the Arsenal, that looks like a good matchup with the Slayblade. No personal experience, but both are supposed to be All-Mountain (stiffer). Just stay away from the United this year.
*I've heard a lot of talk about conversion equipment though, so eventually you should be able to use other brands with the board.