Hello Russell,
I haven't heard all makes of Peltier chipped cool boxes, but those I have are all nosier than I think they should be. Basically it is the rather cheap fans they use.
You can get three way fuelled cool boxes that use the absorption method like most caravan fridges. These are effectively silent, but they also tend to be externally larger and heavier and more expensive, but they also work better. More likely available from camping shops.
I have one and I use it at home to keep drinks in - keeps the main fridge less cluttered.