Its way better than the colors, because of the bass the mini can hold. Volume wise is better too, I think its a well packaged speaker for the size.
Step-down from the Soundlink? That is a bit more complex, short answer is YES! Long version, you have better volume and cleaner highs plus way more bass in the Soundlink. You do loose some portability and more weight to carry around. It depends on your main purpose, for Sound quality the Soundlink hands down the best. For travel, camping, pool, beach, etc. the Mini is the better choice. The Mini has a little more battery life.
If you want sound quality and don't care that much about portability, also consider the Harman Kardon Onyx.
Harman Kardon - Onyx Studio Portable Bluetooth Speaker - Black
(1,665)