Here's the "before", my raw, unmanaged, Comcast "Blast" 50 down, 10Mbps up connection:
Lots of bandwidth, and when loaded, lots of latency. Baseline latency to the test server is ~14ms. Bufferbloat is adding over 250ms of latency. This is why your connection is crap during big downloads.
Now, PIE does make this better. LOTS better:
From 250ms down to 60-80ms.. 1/4 the latency. Not bad, but not great, either. It's still 3-4x the latency that it could have:
fq_codel simply erases all the latency on a connection like this. And this was over a 4 minute sustained test. Able to push over 50Mbps downstream, and over 10Mbps upstream as the numbers in the middle graph are achieved data rates, not including the TCP ACK packets or other overhead.
So, yeah, PIE.
It's ok. But I like fq_codel a LOT better.