Just got one of these off of eBay, no instructions but I can get them online. Tried it and didn't fill to the max but between the 150ml & 250ml mark, as it started to warm and froth it over flowed the top and started running down the sides! If anyone has one is this normal?

Don't worry have just read instructions (normally always read before operation) and I probably overfilled.

> I probably overfilled

Sounds like it.  I have a Nespresso Aerocino - similar thing - and it does the same sometimes.  I also notice that the colder the milk, the more likely is is to overflow AND low fat milk is also more prone

I generally solve the problem by not filling to the line - despite their advice!!