Once they finally get their sync working out of the box, that’s probably where I’ll be permanently.
Well with the exception of Netflix obviously…
Although Firefox has always been my goto, Vivaldi has found a niche in my heart and it’s good to hear that it is well considered here too! 
Just wanted to add that among the features that make Vivaldi stand out imop, can be highlighted the various innovations that have been brought about in such a short time, the community forum and extensions that are better now (always imho) than Firefox (that still has no FEBE or dignified replacement).
To be honest, the only thing keeping me with Chrome is Sync. Once Vivaldi has it implemented I would gladly switch to it.
Thanks all - Firefox will now be the default browser in 18.10 due to the overwhelming vote for it.
Obviously chrome/chromium/vivaldi browser can be installed through the budgie-welcome browser ballot that appears on first logon on a new install.