They were good (and still are), but not always the best value, they were a high end board and came at a slight premium, but that premium got you a board that lasted. Todays boards aren't really built to last like that anymore. Would I buy a Filco today? If I needed/wanted a reliable board that will last 20 years even in a harsh environment, absolutely (just replace the keycaps).
At one time you could replace every part of a Filco with aftermarket parts (mine is pretty much only the pcb), that stuff is still out there just hard to find.
Would I buy one to mod, probably not. They were the modders keyboard back then because of the quality, it could handle being desoldered by a novice and that plethora of aftermarket of parts, but that aftermarket doesn't exist anymore. At the time full custom keyboards and even programmability was rare and this was a way to get a programmable custom without the risk, though both options were very expensive.
A lot has changed and you can get nice boards (for a lot less) that will still last a decade or more with a lot less effort and with a lot more features. Remember these use Costar stabs which need a LOT of work to get to work well and sound good, unlike Cherry where you have multiple options and some improvements over the decades since they were designed, USB type-C, rgb lighting, a ton of layouts and case styles, and many are programmable without changing the controller (Costar boards have a replaceable daughter board and the aftermarket offered programmable controllers).
I still like mine, I still use it as a backup, I'll probably never get rid of it, but I wouldn't build it again even if the parts were still sold, most are not. The main reason being that for the total cost to reach this level you could buy several nice keyboards.
Current parts list:
Vortex Case - squared up, blasted finish removed, pained metalic/candy red, Winkey blockoff plate, hex socket screws
Custom feet - Early Vortex cases came with no feet due to a mixup
Cherry Jailhouse Blues w/lubed/clipped Cherry light springs, 40g actuation/55g(?) bottom out
HID Liberator programmable controller
Stainless Steel Universal Plate (group buy), allows switch top removal, extra thick and needed to be ground in order to fit the stabs
3d printed adapters, the group buy plate is flat and the way these cases work is they need a bent edge to clamp onto, these replace the bent edge.
Type C pigtail adapter and Netdot Gen10 magnetic cable
Foam sound dampened,
HK Gaming Thick PBT caps (o-ringed to shorten Jailhouse Blues excess travel)
Lots of lube...
Total weight, nearly 8 pounds.
BTW,
Beware the Filco ping.
It's not really Filco's fault, it's the crappy Cherry springs pinging and being amplified by the Filco plate design. If you do desolder it, have new (good) springs (or switches) on hand ready to go in.
Also, the WASD case should fit the Filco.
When the Vortex aluminum case for the Filco came out some people tried putting the WASD keyboard inside, WASD and Filco were/are both Diatech/Costar keyboards, however the plate on the WASD was about 1-2mm too wide to sit on the shelf that the plate rests on. Why was it different, who knows, but that was the only thing stopping it from going into the case. The WASD and Vortex cases are identical, probably even made by Vortex, being designed to fit the WASD, the Filco should nest inside with about 1-2mm of room on the side to spare. It won't wobble or move, the top case clamps down onto the plate holding it in pace, it's probably the most solid mounted plate in keyboard history. No guarantees though and you may need to hack up the cord to work with the WASD daughter board but it should work. If not, it should only require very minimal modding to make it work.
