What are some alternatives?
When comparing SHAREit and FilePizza, you can also consider the following products
Send Anywhere - Send whatever you want, wherever you want
qBittorrent - Lightweight and open source torrent client that runs on all major platforms.
Dukto R6 - Dukto is an easy file transfer tool designed for LAN use.
Transmission - Transmission has the features you expect in a BitTorrent client: encryption, a web-based interface...
AirDroid - Access Android phone/tablet from computer remotely and securely. Manage SMS, files, photos and videos, WhatsApp, Line, WeChat and more on computer.
Deluge - Deluge is a full-featured BitTorrent client for Linux, Unix and Windows.