I recently bought the TP-link n200 extenders for my computer. I was getting around 15-20mbps with a wifi adapter, when I originally set up the extenders I was getting 28-30 mbps, but then a day later it dropped to 16mbps and has never gotten back up to what it was before. I know its not a router/modem issue because when I use my other computer which has a direct ethernet connection to the router, I will get 55mbps.