said by quetwo:
Unless he has Verizon's partnership, he won't get 300Mbps down on anything. Verizon has to bond the connections (aka load-balance), or data will only come in the route that requested it. Sure, he could load-balance the requests on his side, but he won't ever see more than 150 Mbps on one download.
Same theory when people "shotgunned" connections to the internet back in the dial-up days. ISPs that actually supported shotgunning (like NetCom) let you get "56k x 2", where others were "56k, but two connections". There was a difference.
Oh, and software routing is /slow/. He'd be much better off getting a used Juniper / Extreme / Cisco router that can do basic routing and NAT in ASICs.
If he uses a download manager and initiate multiple connections, he can get it. Some speedtest.net sites use multiple connections as well, hence how he got 300+ on the download.
Not to mention bittorrent and news sites use multiple connections as well, which he could round robin outbound so the requests come back over both links as well.
This is what I used to do with multiple connections, first starting with DD-WRT and moving on to Linux.--
Dream as if you'll live forever, live as if you'll die today.
Disclaimer: These are MY comments, my employer cant be held responsible.