I agree with above advice -- deposit it directly with VG. My checks lately haven't had holds put on them, but I think that may be because most of my checks are written on banks in the same state. A few years ago I did business with a company based on the opposite coast and it took about a week to clear each check.
I give VG direct access to my checking account, so I can transfer money into VG quickly. I'm not sure why it's different from a wire transfer, but that's not the option I choose. Anyway, I place an order with Vanguard, and within 3 days, it's debited from my bank account -- but the transaction hits Vanguard immediately -- so in effect, they're floating the cash for me.