Tri you can't really put Netweather and XC on the same forecasting level as the Met Office. The Met Office are our national forecasters and part of the civil service. They run their on model suites on supercomputers. They feed in data into the NHS and various other important national infrastructure.
Netweather and XC use other peoples models and in the case of Netweather put their own interpretation on them. Its not to say that the people at Netweather aren't skilled, they are very skilled and half of what goes on in forecasting is interpretation of models. For that though, you need to look at the worded forecasts, not the pictograms that are auto generated.
In all cases, sometimes there are situations where weather is very hard to forecast and this really shows in snow. Just a tiny change in something like the temperature, position of weather system, dew points, et etc are game changers in terms of what people see on the ground.