After we launched self-migration in our KiwiVM panel, the nodes that were running on conventional hard drives (non-SSD nodes) were thrashed quite badly... like 10 minutes after the announcement, so we had to put some limits.
But overall, my observation is that established customers tend to not perform any migrations as IP change is a pain. New customers jump a LOT though - we have customers who switch a 4-5 times per hour - looks like they are testing things from different locations and picking the best spot for their needs.