I've joined this party a little late. I didn't know about Seanan McGuire until I read the serious and pain-filled "Rosemary and Rue"a few months ago.
"Discount Armageddon" is almost the mirror image of "Rosemary and Rue". It's fast, light and witty in a superficial denying-the-danger kind of way. It reaches for sassy, willfully unconventional and effortlessly lethal and makes it most of the time.
It has a great opening line:
"I really don't think you should put your hand inside the manticore, dear. You don't know where its been."
It's sprinkled with clever descriptions that made me smile. Here are a couple of examples:
Verity Price on her unconventional childhood
"Other kids got chores and teddy bears; we got gun safety classes and heavy weaponry. Normal’s what you make it."
Verity on first encountering the straight-laced but soon to be undone Covenant new-crusader-in-town who has snared her on a rooftop:
"Straightening, he puffed out his chest and said, “I am armored with righteousness.” 'Does righteousness protect you from small-caliber bullets?'"
I loved the premise of a family leaving the God-Wants-Us-To-Kill-The-Monsters cult and becoming cryptozoologists working with the Cryptids/monsters to create a stable ecosystem - how on message is that. The plot was clever without being too demanding. The originality and variety of cryptids encountered were fun. The mice were cute. The ballroom dancing was... exotic.
At times, I thought the pace lagged a little. The sex was eye-rolling but I'm almost sure that was intentional.
In the end, much depended on whether you liked Verity Price and cared what happened to her. I decided that I did and that I want to know more - in small doses - so I'm signing on for the next book in the series.