In my opinion, its a bad team.
You can't just lower their atk/spatk, you also have to boost yours. Also, you can steal their held itens and change their ability in case they have moxie, unaware, etc...
I use:
Staraptor bold intimidate, with feather dance, recover, whirlwind and sand attack
Gliscor, mine is bold, just to use knock off, sometimes sand attack and stealth rock, and rarely toxic.
Ferrothorn, worry seed, protect, thunder wave, stealth rock
Furret, for baton pass. You can also use mew, gorebyss, etc...
Conkeldurr, for obvious reasons.
Clefable, mostly in critical situations, you can also use snorlax.
In case the bosses uses a spatk pokemon, switch staraptor and gliscor for:
Electrode calm, eerie impulse, flash, light screen, and sometimes toxic id useful as well.
Klefki, with thunder wave, thief, and walls
Thats the team i use, rarely lose.