I researched sound amplification stethoscopes for a little over a year before deciding to buy the Eko Core Digital Attachement. Several factors led to this decision. Pros: it attaches directly to my existing stethoscope. Sound amplification is great enough. Noise cancelling ability. Small, compact, lightweight, and durable. Long life and rapid charge time with auto-off. Very short lerning curve. App connectivity and ability to share. Cons: the button is easy to accuate on accident. Nosie cancelling could be improved. No cover for the USB charging port. No storage or carrying case. As you can see. My pros far outweigh my short cons list. The device is spectacular and I was amazed from th every first patient. I love that the frequency pickup can be focused on high or low frequency sounds to facilitate auscultation of heart sounds or lung sounds. I opted to go with this one, because I already have a stethoscope that it would fit on and I do not need EKG waveform capabilities. I am an EMS provider and it works wonderfully in the back of my MICU, patient's home, outside, or moderate to loud environment. I would highly recommend this if you are looking to upgrade your current stethoscope.