Prime Now, Amazon’s ultra-fast delivery service, launched in Denver on Thursday, and of course we had to try it out for ourselves.

We placed two orders right around 10 a.m. Thursday and chose free two-hour delivery for both.

Order No. 1, an Echo Dot (on sale!), was placed at 10:02 a.m. with expected delivery between noon to 2 p.m. Shockingly, the first address that popped up in the Prime Now app was The Denver Post, even though the buyer had never had an item shipped to the office before. Without further notice, our new Echo arrived in a brown paper bag by 12:35 p.m.

Order No. 2 was five pretty random grocery items from Sprouts Farmers Market, which is working with Prime Now to offer free two-hour delivery. We placed the order — an 8-pack of LaCroix (grapefruit flavored, of course), Annie’s Homegrown Organic Cheddar Snack Mix, green onions, raw almonds and Julie’s Organic Vanilla Ice Cream Sandwiches — at 10:02 a.m. with expected delivery between noon to 2 p.m. A text message from “your Prime Now shopper” arrived at 10:40 a.m. informing us that they had started work on our order and would let us know if there were any changes. Three paper bags were delivered to The Post’s front desk a few minutes before 2 p.m.

Here’s what we learned:

There’s a minimum order amount.

And it’s $20. Also, you can’t combine items from Amazon and Sprouts Farmers Market to get to your $20. In other words, you’ve got to buy $20 worth of stuff sold by Amazon or $20 worth of stuff sold by Sprouts to qualify. (Amazon and Sprouts both sell fresh grocery items, too.)

Centennial residents need not apply.

Not all of the Denver metro area was included in Prime Now’s service area as of Thursday. A coworker who lives in Centennial entered her ZIP code in the morning and got a “We do not yet deliver to” message. In a quick test of ZIP codes, some other south metro locations, including Parker and Highlands Ranch, were also excluded from the delivery area, while north metro locations like Westminster, Boulder and Lafayette were good to go.

You’ll likely be waiting longer than two hours for your stuff.

On both of our orders, it was delivery within a two-hour window, not two-hour delivery. Checking out around 10 a.m., the first available delivery slot was between noon and 2 p.m. By the time the second order showed up just before 2 p.m., it had been close to four hours since we made the purchases.

Tipping is automatic, but optional.

A default $5 tip was added automatically to both of our orders. You can change it (or zero it out entirely) if you want, though. Per Prime Now’s FAQ section: “Tipping is completely optional and can be changed up to 24 hours after delivery for orders other than those from Amazon Restaurants. Your entire tip goes to your courier, but information about your tip, such as the amount or who has issued it, isn’t shared.”