It generally works at around $8 to $65 per gigabyte (depending on your data plan, fees, and taxes). With an FHD stream using up to 3 GB an hour, the real question you need to ask yourself is how does $20 to $200 per movie work for you? I have no idea how it works through the BRV, but it works through my 5510L Jetpack just fine.
> Does anyone use the 4g lte router, together, with something like amazon fire or roku ?
While I do not have a 4G LTE router I can confirm that it does work with amazon fire and roku. All you need to do is get a wireless compatible fire or roku and you will be good to go. These devices wont care if the internet is coming from your 4G LTE Router, Landline cable connection or something else. To them WiFi is WiFi and internet is internet, the 4G LTE router makes no difference.
> How has that worked?
While my previous statement suggests that there are no compatibility/technology issues with connecting a 4G LTE Router with a personal mobile device we generally suggest against doing so as your primary source of internet. Verizon devices are on metered data accounts. When you open yourself up to streaming content and treat the VZW device as your primary internet connection you make yourself vulnerable to overage charges. Understanding and troubleshooting overage charges is the number one issue and has been for a long time. It is much safer to use a normal unmetered/unlimited/high data limit connection like a local DSL or Coax connection instead. Fall back on the 4G LTE router as a backup or for everything else.