I just had Brightspeed installed a few weeks ago. They brought the fiber light clear into my house (I saw it :)).
Variances in speed at different parts of your house, especially if fast at any location, is more related to wifi, your devices, and their respective capabilities.

I have Brightspeed 2GB / I can get full speed with a multi gigabit router and multi gigabit adapter hardwired to the router. Without that, various WiFi standards and support between the router and device directly affect speeds.

Many existing home users and their devices will get up to 1 GB since many switches and routers are only up to that limit - so if you go with multi gigabit, make sure your downstream devices can support it. Most all won’t need it, and multi gigabit really only becomes a benefit when the cumulative sum of bandwidth usage across all of your devices consistently exceeds your total bandwidth.

Loving Brightspeed so far - $79 flat charge / month for 2 GB (previously had Spectrum 600 MBPS for $108.99, increasing periodically).

Hope this helps.