According to your query the “SPEED”, it is truly say almost same. It is best to visit the following links and clarify them….Here’s the link for N300 Wireless
and for N600 Wireless.
After navigating select “Product Specs” tab.
Hope it helps you!
The Wireless N technology will support the “speeds” listed, as long as certain criteria are met. A router that has one antenna and transmits on one channel (known as 1×1) will not be as good as a full-blown 3×3 (3 antenna, 3 channels)
Unfortunately, the marketing folks of wireless router manufacturers aren’t really good at indicating what type of router you’re really buying. Most “home” routers are 1×2, or even 2×2, whereas the small-business to enterprise levels are 2×2 to 3×2, or even 3×3.
My best suggestion would be to research the models more in-depth and find out what type of N transmission they’re using. The closer to 3×3 that you get, the better the range, signal strength and stability of wireless N signaling