Summary: My mm50 has served well, but its one drawback for me was always having to pack the charger separately for extended trips, as it didn't fit in the carry pouch. The Pure-Fi corrects this oversight, without increasing the pouch's size dramatically (it's an inch longer).


Another added feature is the remote's ability to control iPod functions. Of course, you have to be close enough to the unit to see the iPod's display, and you'll still want to use the scroll wheel to quickly browse large libraries, so the additional remote functions don't eliminate the need to work the iPod directly. Still, the remote is more useful than the mm50's. Unfortunately, I find that almost a third of the time the unit won't respond to button presses - I don't know if this is caused by a balky remote or a flaky IR receiver, but either way, it's annoying.


You can use all iPods from 3G to the present by installing one of the included dock inserts. Unfortunately, the dock inserts don't fit securely, which allows a certain amount of iPod movement when using the click wheel. I'm concerned that the flexing may eventually damage the iPod's connector.


Ultimately, the sound is what counts, and after extended side-by-side listening tests with the mm50 (yes, I have more than one iPod!) using a variety of program material, I have to give the nod to the mm50. While both units provide very pleasing sound, the Pure-Fi's louder volume is apparently attained by emphasizing midrange frequencies, resulting in less \"air\". The difference can be subtle, but I find the mm50 consistently provides more balanced and natural sound.


So, for current mm50 owners, is the Pure-Fi worth it? Might be a tough call - depends on how critical a listener you are. It can produce a little more volume, which would make it better suited for use in larger rooms or outdoors compared to the mm50. (If you're not too picky about sonic accuracy, the Altec Lansing iM9 is louder and better suited for outdoor use.) If you're using it in close quarters at lower volumes, the mm50 is superior. However, for those who are looking for their first portable iPod speaker system, the Pure-Fi is definitely worth consideration.

Summary: A very excellent speaker all around. It has very good sound for a speaker of it's size. It also has a unique remote that I often use that lets you navigate songs and menus. The remote makes this speaker even better. However on my iPod Touch the remote scrolls down two songs at a time on the menu, this issue did not happen on an iPod Nano 3rd generation.