As a Halo fan myself, I don't have faith when Microsoft is naming its new Web browser and its various features from one of its best-selling gaming franchises. It seems like a scam to get people into buying into another terrible browser. I'll hop on if it's on part with Chrome or better, but I doubt it will be.
It's free. They're not trying to make you buy a browser, it's to replace Internet Explorer.
IE will still exist but only as a secondary browser for compatibility reasons. Also Spartan was simply a codename, it's now called Microsoft Edge, derived from "bleeding edge", with logo:
Not the biggest fan of the logo to be honest, it's pretty terrible, but I suppose the big blue 'E' is quite iconic and to some less tech-savvy people that means Internet.
Picture of it in motion,
Clicky!
Reviews about Edge have been alright I guess. They've been saying it's definitely a big improvement over IE, but not some huge step-up for browsers in general, it's pretty much on par with Chrome and Firefox now, and if you like either of them there's no real reason to switch. With that said it's still in Beta so that might change, might get better, or as Techradar put it "sharpen up", hurr hurr.