Manjaro Budgie or Ubuntu Budgie
If not solus, what distro would you be using
I would have probably stayed with Manjaro. Linux Mint would be a good option too.
It would probably have been Manjaro, as I migrated away from Arch because of problems I had setting it up.
Devuan and I3 or slackware and fvwm
In addition to Solus, I also run Debian Stable and Debian Unstable, all with the Openbox window manager and the Tint2 panel.
I would be somewhere in Arch, but probably not on Arch itself. I'm liking Arcolinux at the moment.
Probably Manjaro. I play a lot of games o my PC and i use a Vega 64 so having an up to date kernel, Mesa and its dependencies is the way to go.
But I prefer Solus's more curated rolling release model. On the edge but not the bleeding edge.
id probably be back on distrowatch looking for the perfect distro, while using one i wasnt completely happy with
which is how i found solus
Probably Ubuntu or Antergos.
So far I using Solus is the longest ever. if not solus maybe I would try Elementary OS or back to Winwow01 
Bunsenlabs
Crunchbangplusplus
Archbang
Clearlinux
Archlabs is what I was running prior to Solus. I would go back to an Arch variant.
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I shudder to think what other distro I'd be using if not Solus 
But if I had to, I'd probably be using Fedora or KDE Neon or attempt my hand at Arch. For the record though, none of these distros offer the same stability that Solus has, so thankfully I can compute in peace.
How about building a brand new distribution and calling it Wind ?
Wind OS sound nice 
I'd probably be using MX or Manjaro. There are so many "okay" distros, but only one Solus!
If not Solus, perhaps Linux Lite. Or Q4OS.
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I have openSUSE installed in parallel, mainly because of CUDA support.
I never did a "Linux from Scratch" so maybe that. Or fully move on to OpenBSD.
Probably stayed on w10