That is a very solid argument against OPNSense! I do wonder if the advent of AI can be used to fix issues like this, but in the meantime I totally see why you would choose OpenWRT.

For some real numbers, I picked up a 2018 generic office PC (Core i5-7500) used for $50 as a backup machine to run linux on when my laptop was in for repairs, and it idles at 14 W, vs the OpenWrt One which appears to run at 5.5 W.

So that's 10 kWh/mo for the PC vs 4 kWh/mo for the OpenWrt One.

I currently use an old boring HP tower. Nothing fancy, I think it’s a quad core AMD APU. But if building it from scratch I would get a $35 thin client off eBay and stick a NIC in it. The CPU load is minimal as the network card does all the processing. I do have 8 TP-Link access points and a hardware controller as well as three unmanaged PoE switches for the Wi-Fi but that would be the case regardless of what my router is.

>however using an old PC as a router almost certainly wastes an enormous among of power

I don't think you're quite right on this, or at least you're imagining using something inappropriate when the comparison here involves buying something new right? So it's not "OpenWrt One" vs "whatever you happen to have in your closet" but "OpenWrt One (~$110-130)" vs "whatever can be bought used for $110-130, if you have nothing appropriate". And while they won't go to near-zero like some ARM stuff might, idle power for PCs improved a ton after around the 2013 era. There are lots and lots of small systems available for equivalent prices on Ebay or the like made since then (like Intel NUCs or various other mini PCs) that will idle around 4-10W. Like to take something in the same price range as this OpenWrt One, I regularly see 7th gen era NUCs going for <$140. An i5-7260U will have single threaded performance about the same as the MediaTek in this unit and multi-thread close, but will also generally have 8-16 GB of RAM and often a 250-500GB NVMe drive as well. It'll probably have only one native ethernet, but USB or TB adapters work fine with Linux & FreeBSD at this point.

There's definitely a question of values and exactly what you're trying to focus on, but there are a lot of niceties in having lots of RAM on tap and extremely standard fallbacks to interface with a system, back it up, etc.

>or an OpenWrt One which will possibly also have newer, faster WiFi standards (WiFi 6)

If you want an AIO style device that's definitely a consideration, though again USB WiFi dongles are a thing too. But regardless of router choice, for someone considering going beyond what their ISP offers at all I think it's usually well worth spending the $50-80 to get a dedicated wireless access point. It'll make a major difference in real world performance in most spaces I've seen to just physically have a unit in an ideal spot (on a ceiling or high up on a wall, away from metal). Aesthetically the clean disks or rectangles those tend to have also blend well and mean that various boxes can be tucked away. And of course you get to upgrade networking bits separately from your router.

Anyway, definitely good there are multiple approaches, this is an area of life where people can have very different needs driven by very different physical environments and "stakeholders" (like significant others). But I think OPNsense (or other bog-standard-PC FOSS alternatives like VyOS) can be competitive even in TCO, depending on how much value you place on pushing your networking stack and what else you have going on (like solar power).

I use an m920q as my router and it idles around 5W.

That makes sense, but I really do have to emphasize just how gloriously stable my old PC router setup was.

It was the most incredibly hassle free router I've ever had.

Hopefully, the OpenWrt One is like that. But if not, I'm going to go back to killing the planet with my loud ass beater PC.

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