I have 2 of them. I have the Piko-1, and I loved it until it went fruity on me. It was very accurate until it flipped out...I now have a SpiroPd...and at first was impressed with it but now not so sure. I like that I can download the results however it doesn't pick up when she coughs like it is suppose to. And she hates it because the Piko-1 you blew one time and that was it....the SpiroPd she has to do 3 blows before it will spit out a reading... so I haven't had a chance to test the SpiroPd with the clinic yet but I did the Piko-1 and it was spot on. And I knew when it went crazy cause it was giving off the wall high numbers that I could only dream she was blowing LOL! I wanted to get the Piko-6 because it gives more detail but at the time I purchased it the company I purchased from was out of stock and I needed it ASAP. I think it would be a good buy!! Also if you get it and end up liking it...you can buy the device that lets you download to the computer as well.