Phil has suggested that I try https://f8lure.mouselike.org/ as well - I've left a trace running overnight and the difference between that and the BQM is remarkable (see attachment, BQM trace still has frequent peaks to around 20-30ms). So I guess what I've been seeing could be the result of congestion somewhere between Giganet and the ISP that Thinkbroadband uses, which probably shows that there will be quite a bit of variation in real life.

Edited by Stargazer99 (Wed 19-Oct-22 09:26:42)