sorry.... I took the detour to "privacy features" which is a lot bigger [LOT] than browserology.
btw - will new IE have sync'ing?
on android and IOS I much prefer Dolphin. its probably the fastest, most stable, and most customizable browser I've used. smartly, they don't want to fool with a fast shrinking PC market.
I Like IE for youtube, of all things, because it is demonstrably more efficient with youtube. that said, it is probably not true on desktops with dedicated vid cards [good ones, that is..]. Chrome is awful of late, efficiency-wise, but what its good at is speed among a lot of open tabs as long as vids are stopped [flash objects "click to play".... would be a nice feature for IE-n]
its also quick to coherency - browsers in general these days try to trick the appearance of being "fast to start" but it ain't so. FFox's latest is a long wait - take a bathroom break. Chrome is legit fast on the first search or address input.
opera is too slow to matter - that is from a dead start, and apparently no one there is ever going to fix the awful bookmarks management - dreadful.
in the past I hated IE ["internet exploder"] and counseled all my dependencies to avoid - but those days are past for me. no hate. good for some tasks.
All true but: You could say that Windows 7 will eventually get Spartan because all Windows 7 users will be able to update for free to Windows 10 which will get spartan...
I don't think MS will make Spartan available for Windows 7. MS is trying their best to get Windows 7 users to upgrade to 10.