That, and the WikiIn that case, I do not think I have ever set my HPF higher than 100 hz (and that includes using it on guitar where I set it higher). For the LPF side, I do not think I have ever gone lower than around 5khz. Noting I mainly use the LPF to get rid of some effect noise and string noise when I plug in an acoustic bass. Noting that I am one datapoint, but absolutely agree that the range on some of them is much larger than it needs to be.
The first post in this thread may also be worth a read if you have not already. I know it helped me when I was first buying one. High Pass Filter (HPF) and Low Pass Filter (LPF) Mega Thread
High Pass and Low Pass Filters | TalkBass.com
