Yes, but only slightly. No matter what VPN service you use, you will almost always have to settle for an internet speed that would be less than normal. That is because while connected to a VPN, your traffic is encrypted on the client side, decrypted on the server side, has extra headers and meta data added to it, and often has to take a longer route to the destination site or content. All this causes an increase in its latency. However, quality VPN services like FalcoVPN do their best to keep the drop in internet speed to a minimum.