I also find the new maps extremely slow on desktop, though the interface is reasonably fast on mobile. Tried both Firefox and Safari on my mid-2010 Macbook Pro,

I also find the new maps extremely slow on desktop, though the interface is reasonably fast on mobile. Tried both Firefox and Safari on my mid-2010 Macbook Pro, and everything is pretty wonky and unreliable. I actually use Bing Maps now by default on desktop due to the speed issue, unless I need something that Bing doesn't have (Google has much better transit coverage, for example).