I use a NDD Medical handheld spirometer - costs a couple of dollars per test and prints report (pdf and import) - works great and can even take to nursing home, etc.
I think the cost of an interface and how much Midmark costs is ridiculous (I paid less than 1500 with software, cradle and 50 mouthpieces I believe). That being said I have been talking with Josephine at AC (in charge of interfaces) and will keep pushing to develop an interface just to make it easier.
