I think a lot of centres tend to go for no more than 2 pumps - Roche and Medtronic seem to be quite popular - but there are others on the list too.
Some PCTs will have you jumping through hoops of fire to even be considered for pump therapy, others less so. But it does require commitment and work from the patient, so I guess they want to ensure they're not wasting the considerable initial investment and ongoing cost for consumables.
