Battery mod,Speaker mod have not that much pros to see it as an complete alternative to powerpack, Bluetooth speaker.

Battery mod is good but crippling newer gen with less battery shows how much the company is making people to settle on another flagship or buying the old gen Zforce/play(The only good point i see in Battery mod is no hassle of wires & efficiency mode{although there is no research or long usage review of anyone stating multiple charges to 80% will degrade/how much it will impact on the internal battery even more)

Weight & thickness would be issue always so even making a phone 3mm thin they'd still have weight & thickness issues.Internal battery is more efficient than an external battery charging

Speaker mod on the other hand is great if you can get it for less than $50.If it had a headphones jack(even a normal one) on the top,It would have been a great thing to correct the mistake Motorola did by removing headphone jack.

Zplay users would've got another jack,Thus giving them option to have the phone straight into the pocket with earphones attached/ability to plug in 2 earphones.

However again weight & thickness of it becomes an issue.I personally like the thickness & weight of it because i commute to college by train so it being heavy & thick gives me relief knowing that it would not be easily pickpocket ed easily as compared to slim & light weight phone which one would only feel missing from his pocket when he checks it.There's even space in the camera cutout to grip by the index finger to feel the phone secured & grip as well.

If one has a Bluetooth speaker there hardly is any reason to upgrade to even Soundboost2 speaker mod.I don't have a Bluetooth speaker & i considered getting soundboost mod because i got it at a good price & didn't wanted to always carry a Bluetooth speaker around & had not that much better speakers in my price range anyway.