Took my cat in recently. He was not going to the bathroom and lethargic. He had a blocked urethra before so I was nervous (Yes, I'm overly concerned about my pets). They weren't crowded and took him back right away. There's no guarantee of this because it really depends on how many emergencies are there.
Good news - nothing wrong with him. And they were super nice, friendly and caring. From the time I walked in the door till the vet tech waved me good bye, it was such a friendly place. I highly recommend them.