Just to let people know, I successfully loaded my card with £5k yesterday to make a big flight booking, and had no problems at all. So it looks like loading the card, even with big amounts, doesn't raise any eyebrows at Lloyds.

I'm actually really annoyed about the flight booking. I was trying to jump on the FRA-LAS bargain CW fares (£1500rtn), but the prices changed on the BA website as I was booking. I managed to get it to price and book on eBookers, but they charged me in £ whereas BA would have charged me in EUR. That couple of minutes ultimately cost me 75k bonus Avios...