Limewire Pro does improve search results and allows for faster downloads. However, if you're downloading from someone with limited bandwidth, there is nothing LW can do to make them faster.

All p-p programs have the same issue; they cannot control what another peer wants to share, even if it is copyrighted, misnamed, and contains trojans or child porn. You can give any name to a file and share it on the network. This freedom to share comes at the price of having to defend ourselves from uncontrolled content. Hence, we recommend using LW's filter along with PeerGuardian and Bitzi.

There are commercial services that guarantee safe and fast downloads of whatever you want. They tend to cost much more than LW Pro.