Quality:
It's built like a brick outhouse, has good switching components and is an excellent value. But if you have any taste or experience with tone, scrap the junk Chinese 12AX7 in favor of a 5751. Even an EH or Tesla 12AX7 is too hot in this pedal, IMHO.

Value:
Great value!

Sound:
In stock form, this is a heavy metal player's pedal, as noted on page 1 of the manual. If you are a true connoisseur of tubes with real life experience, you will hate this pedal in stock form. The junk Chinese 12AX7 is shrill, brittle and has no headroom. Even with the gain at 50 percent, it's distorted enough to play most any heavy metal. If you want to improve the sound TENFOLD, give the stock tube to one of your tone deaf buddies and install a 5751. It's 30 percent less on the gain scale than a 12AX7 and alive with warmth, character, headroom and more clarity than you can imagine. Plus it still gets distorted enough to do anything you want. This pedal did not impress me in the slightest until I did this, and once I did, it was night and day.

Ease of Use:
Plug & play!

Overall:
If you're a blues player, or versatile in what kind of rock you play, BE PREPARED TO SWAP TUBES. Keep in mind it's easy and not expensive. If you get this thinking it's a tube amp in a box, not even close in character without a swap!