Oh, sorry. I forgot to mention last time. If you grab the MMA pack (which I recommend for it's high quality animations), then you'll still need models. There are a few free human models packs from the same guys:
https://www.assetstore.unity3d.com/en/#!/content/127
https://www.assetstore.unity3d.com/en/#!/content/124
https://www.assetstore.unity3d.com/en/#!/content/122
The MMA animations will work with any models that are mecanim compatible, so all the above should work.
That bikers gang pack looks OK and does come in many formats. But there's no way to confirm if it's mecanim compatible or not. If it's not compatible, you're potentially wasting money on animations you can't use.
Mecanim isn't the only way to have animations of course, as UFE does support legacy animation system.
The pack will "work", but that depends on what you mean by "will it work". Any 3D model with any animation/rig system will work. But if it's not mecanim compatible, then it won't offer you the nice mecanim features (easily share animations between models, get animations from mixamo store, visual blend trees for custom animations etc).