The US catalogue is the largest, gets new releases first and has the most 4K and Dolby Vision titles. The trade-off is distance: US routes cross the longest path, so they wobble more at peak hours. Prefer an IEPL dedicated route — once jitter is under control, 4K holds steady.
Japan updates anime and local productions quickly, and some series are only listed there. Routes to Japan are physically close, so a relay route usually has low enough latency; there is no need to put everything on a dedicated line.
Hong Kong and Singapore carry a high share of Chinese subtitles; the catalogue is smaller than the US one but covers the popular titles. Singapore routes connect better to Southeast and South Asian platforms, which suits watching several regions at once.
The UK direction mainly serves local broadcasters such as BBC iPlayer. These platforms are strict about where the exit is registered; when it fails, switch to another route in the same region rather than reconnecting to the same one — repeated failures add to the risk flag.