Final roundup........
All outstanding orders have been fulfilled so (fwiw) here's my short term thoughts on the KB's and switches I've tried....
First up, both the wired and wireless version of the Royal Kludge RK84 did not disappoint. It's not a metal case, but being plastic is the only real complaint I could come up with on the KB as a platform. It feels substantial and I'd be hard pressed to call it anything but premium. Most recent versions of the RK84 come with foam inserts which appear to do a good job of cutting down any audible unpleasantness from the keys bottoming out.
It's possible that I'm missing out, but my experience with both keyboards under stock conditions is good enough that I don't feel the urge to attempt any mods outside of replacing the switches, and possibly keycaps. The stock keycaps are OK, but they aren't very heavy and have thin(ish) walls. I do prefer the MSA profile keycaps I threw onto the first (wired) KB, but the stock keys have the benefit of both RGB passthrough (which most switches will support) as well as preserving the RK84's special function markings.
The GMK67 I ordered from Aliexpress doesn't feel (or look) quite as premium, but it too appears to have decent enough filler that I don't feel I'd gain much by trying any of the available mods. It's a 65% format so it has arrow keys + a rotary volume dial but not an F Key row. I threw Gateron G Pro yellows onto it paired with a cheap set of amazon pudding keycaps and don't mind the typing experience on it at all.
Overall, going to these hot swappable mechanical keyboards from my Corsair Reds (a K70 and a K65) has been an absolute eye opener. I don't know if it's because the reds are so light, or if the bodies are the culprit (I suspect a combination of both), but they feel and sound cheap by comparison regardless of the switches I've thrown onto the new boards.
Now to switches.....
Hands down, the Oil Kings were my favorite out of the ones I tried with the yellows probably second. I'm thinking the Oil Kings are the weight I'd dial in if I had the option, and without a doubt they do feel a bit smoother than any of the stock G Pros I've tried. I'm just not sure they're worth 3X the stock gaterons.
I've just started using the G Pro blacks on the new keyboard and while I like the muted sound I'm getting out of them, I'm thinking 60 might be just one step too far (the oil kings are 55). I'll have to see if they grow on me, and if not decide if I want to drop the coin for Oil Kings + Keycaps (can't read the stock keycaps with Oil Kings), or drop down to Yellows.
I guess I'm just not a tactile kind of guy.... I preferred the yellows to the browns and even found the yellows felt heavier to me in spite of the specs stating that the browns were the heavier switch.
I tried the RK browns side by side with the Gateron G Pros and honestly couldn't distinguish between the two. I certainly wouldn't recommend anybody replace the stock ones with the Gaterons.
Having said all that....
@Vittra had it right when he suggested that those mixed switch plates probably aren't much use for deciding what switches you prefer. Without splitting the keyboard down the middle to see what typing on different switches feels like it's really hard to distinguish between different switches outside of the basic tactile/clicky/Linear types.
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