The bonus for opening LloydsTSB Duo Avios card accounts
using the link at avios.com is 5x earnings on the AmEx for the first three months, i.e. 5 Avios per £, no minimum, no maximum. 10 Avios/£ for the Premier AmEx.
http://www.avios.com/collect/lloydst...sDW_CollectNav
Using the link via LloydsTSB produces the bonuses already mentioned.
ETA Olly types faster than Roger!