Once again I find myself on a 2+ hour train journey to Leeds. It happens :-)
So, I try and get some work done. I did once try and play WoW, but that really did not work well. For a long time I have used a MiFi. They are excellent. Today I tried a few alternatives, largely because I totally forgot to bring the charger/USB lead for the MiFi...
The first thought was tether via wifi to the iPhone. That would work, but would, in this case, be some horrid Three NAT internet service. One reason for using the MiFi is it can take an A&A data SIM which really "just works" and has a fixed IP and full 1500 byte MTU and so on. Yes, it is also on Three, but a business grade service. It is also then using an IP that is on my LAN at home, which is handy.
I am at a loss as to why Apple do not include a mobile modem in the MacBook Pro - they really should.
So, not using MiFi, I tried the East Coast Trains in-train WiFi. That was a huge mistake! Pings at 3 to 5 seconds, and sometimes 15s. Loads of loss. Unusable for anything interactive (like ssh and vim).
I realised I could tether the iPad mini. It has an A&A data SIM too. That works (via WiFi). But as I want to keep it charged I plugged in the USB lead, and of course the Mac simply tethers by USB, so even better.
The data SIM in the iPad means I am now seeing much more sensible latency, usually under 100ms, and much more reliable connection. I suspect this will be my preferred way of working now rather than using a MiFi at all. It was good while it lasted, but this "just works" too.
But one thing for sure - don't use the in-train WiFi, it is dire.