I'm not sure if they will know ping as they have said that they won't be able to estimate speeds installed. Is it worth asking anyway?
Sure they can't estimate!? - Sounds like they don't know what they are doing. Anyone can estimate, whether it is a good estimate or not is something else.
15GB isn't much usage, not enough for any regular TV streaming.
As long as they are using fibre and have enough capacity then pings will be fine for gaming, voip etc.
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