This review is not written to help sell this product but to give some insight to anyone who might need to invest in a PLB to save your life or the lives of others. Not a tiny investment. I deliberated for some time over buying this unit or a smaller unit and finally decided if I ever have to use it the size and extra money will be the least of my worries. I did test it, and it quickly passed. The GPS can be tested up to 60 times before the software won't let you test it again. A single test would probably suffice. I want GPS coordinates visible since if I have an emergency it will be at sea and the possibility I may be able to reach someone by VHS radio and pass on my coordinates would be invaluable. A photo shows my Standard Horizon radio next to it. The ACR is heavier and bulkier, but it is not the type of thing I would carry with me when I know the Coast Guard is near. This is for extreme outings. Currently there is a rebate in effect through ACR, and this unit comes with a year of 406link.com under the rebate. Also, if you go to the ACR website you can read a number of first hand accounts of being saved through activating a unit. This is serious stuff.I'm a paddler heading out to international waters and understanding how these connect to SAR (search and rescue) satellites and connect rescuers to my individually registered PLB already gives peace of mind. You must register the unit with NOAA and 406link gives you an opportunity to send out preprogrammed emails/texts (I won't know exactly until I get my rebate). Yes, I wish it was smaller, but the ocean is very big, and I want to be found. I tucked both my radio and the PLB into the front pocket of my racing PFD, and while the weight is a little noticeable there isn't much I can do about that. As long as a shark hasn't bitten off both my arms, I will be able to reach it!