Surface Pro 3 Slow WiFi - 72Mbps Max (driver)

My Surface Pro 3 still has slow wifi (in particular download) after July 16 update. I have an old Linksys E1500 router (support B/G/N), and my other Asus laptop constantly gets a 18Mbps download and 5Mbps upload. But my Surface Pro 3 has an abysmal 3Mbps download though same upload. I tried all possible things people discussed in other threads: reverting wifi driver/and or manually reinstalling new driver, changing wifi power plan (via Hyper-V), etc. The speed seemed remained the same and also regardless whether the power is plugged in or on battery. Thus in my case it appears not a problem of a battery power plan. I suspect that it may not work well with my router, as other people have also pointed out. My router was set at a mixed mode initially, but after I switched to Wireless-G only, all of a sudden, my Surface Pro 3 achieved the download speed 18Mbps.

Did anyone else experience the same problem? Can this be solved without changing the setting of a router because you have no control over all those routers out there?

Thanks for reading!

Extremely slow at times.  Reboot seems to set things straight, but who wants to do that a couple of times a day?! Jury's still out.  Have another day or two for a final decision...

Speeds here are intermittently slow. After first connecting to 802.11n, I was getting over 100Mb, when I re-tested later, I was getting less than 3Mb from the same network under similar conditions.

Hello, I am not sure why today the SP3 decided to disconnect from the WiFi every time I put it to sleep (tap on the power button)  When I tap on the power button or press on the windows key, the WiFi shows disconnected and I have to manually reconnect to the WiFi router.  In some instances I have had to reboot the SP3 in order for the network to even work.

As usual, all the other devices in the home are working just fine without issues.  

I even tried rolling the wireless driver back to the 6/3 version and still no luck.  This is something new and no software has been installed.  

Why can't this be solved by now? bit frustrating not being able to even use it.  Any other thing that I can do to make the WiFi work?

Thanks

Downgrading the driver to 24/4/2014 version solved all my WiFi problems! Thank you!