DH has the original, and I have a Mia. I got the original 5 years ago when it was the only unit available. When he started to use it, I just got him his own brush head and we would change them off and on. He because as obsessed as I did when he didn't get bumps from shaving anymore.
Luckily, I was able to win a Mia at work 3ish years ago and that solved our switching problem. At first, I noticed the Mia didn't have as much power (because of the speeds), but then I got used to it. Now with the Mia 2... you have options. I am in love with the deep pore brush head. I use it with Clinique Acne Solutions wash, or Neutrogena's Acne/Redness Gel wash. I like both. I don't have acne, but since I'm oily, I like a good dose of salicylic acid.
My skin definately loves it, and if I forget to charge it for a week... I notice the difference.
I have not purchased a face scrub or a mask since I've had it, simply because I don't need them anymore. The money saved there is significant.
I think it's a great investment. Be sure to register it online and if something happens to it they can replace it.
Rarely do we see any problems with them (I sell them at work), but in 5 years I believe I've seen 2 returned with issues. One wouldn't charge (a year or so ago), and the other was brought back last week... it didn't want to turn on, but then all of a sudden, it turned on by itself and wouldn't turn off! It was possessed!! These are very very rare cases and we took care of them with no issues! If you have any questions

Just ask!