It seems like a great idea and appears to work well, however my concern would be that you'd mostly need a CIR and a suitable aircraft to use it. I couldn't live with myself if little Johnny missed his Chemo therapy because I had bad weather or trouble starting my engine! I note that many of the profiles of the pilots show pretty good aircraft such as twins and Cirrus, etc which would be of benefit for these types of operations, particularly that they are often organised weeks in advance.