The Bad:1) Loose hardware rattling inside the enclosure. It was a loose standoff that appeared to have been for the vacant M.2.2) While fixing that, I learned the onboard PSU wires connect to the bottom of the board at the 12V barrel jack. Both were cold solder joints.3) The default BIOS settings are absurd for the device's purpose. It restricts the already anemic CPU to its absolute minimum performance. It defaults to preventing the unit from powering on automatically after a power outage. The fan setting choices include passive, full-on, or "custom," a fan curve that can't be customized.4) Cooling: Rackmount devices fall into 3 cooling categories: Passive, Front/Rear, and Side/Side cooling. This device doesn't use those configurations. It brings air into the bottom and vents it out the side. Rackmount devices are expected to be mounted with others directly above/below them. This is why rackmount devices never have a Bottom/Top or Bottom/Top-to-Side cooling configuration. Your CPU will roast if you put the air inlet directly against another device in the rack. You must mount it at the bottom, upside-down at the top, or have a 1U gap below it. This relates directly to the next problem.5) Chassis Depth and Ports - This unit has a shallow depth. This means regardless of whether you intend for the USB/Console/Power or the network ports to face the outside of the rack, the ports on the inside will likely be blocked by any other rackmount device unless you put it somewhere in the rack with unobstructed access above or below the unit.6) The power button, which the default settings would require you to press after a power outage, will also be blocked by other devices if it's facing the inside of the rack. Also, the power button can NOT be used to turn the device off. Two ways to power off the device are: 1) Shut down the OS with a full power-off option and 2) Pull the power.7) Serial ports and the UARTs used: I don't know why anyone buying this for its apparent purpose would need six serial ports, primarily when supplied by 8250 UARTs. We gave those up in 1992 because they lacked the buffering and flow control to handle speeds over 9600 bps.8) Power: The N4305 CPU Datasheet indicates a TDP of 15W, but this doesn't mean this product uses 15W, even though they seem to indicate that. I'm seeing 25+ watts, which makes sense because there's more than just the CPU consuming power.The Good:1) The enclosure depth is perfect for the board; it's not too tight, and there is no wasted depth. Caveat: The board is only half wide vs. a 1U rack module. You could build an HA pair of pfSense systems in a different enclosure configuration in 1U. However, because of the cooling and the wasted horizontal space, you would need 4U to have room for the air inlet situation.2) The enclosure is well made; it's not too narrow or too wide; test fitting to various racks revealed no issues like some cheaper 1U devices.3) The rackmount ears can be attached to present either face of the device to the outside of the rack, depending on your needs.4) Even considering all the cons, it simply works. I had no issues putting the pfSense image onto a USB stick, booting it, installing it, and configuring it for my needs. There were no weird driver issues or strange workarounds due to the industrial/bespoke nature of the motherboard or anything.With so many more cons than pros, why 4 Stars and not less?1) It fits my needs for the moment.2) It cost less than the hardware I'd need to purchase to build something comparable from on-hand PC parts.3) Even with higher power consumption than advertised, it uses significantly less power than a similarly configured PC setup.4) It had free 2-day shipping5) It performs as well or better than what it replaced. Unlike the EOL enterprise router it replaced, it has an open path for future software updates.