Pretty phenomenal. The base donut itself is AMAZING.
PROS: Made fresh to order, they come to you super hot, crisp/crunchy on the outside and soft inside. They will glaze and top it however you like when you order it. There's about 20-30 "flavor presets", or you can pick your mix of glazes and toppings. I had a Key Lime Pie, which was a lime glaze, graham cracker crumble and powdered sugar.
CONS: Flavors are a bit inconsistent. The key lime flavor wasn't as strong/tart as I would have liked, but my friend's cookies & creme donut was spot on. Be ready to wait 5-10 minutes for your order, maybe 10-20 for a dozen.
If you're not eating donuts often, you should be springing for these. All in all, great stuff, and well worth your $1.95 apiece or $15 for a dozen.