They're both around the same price, the Bruiser is probably heavier since it's built to take abuse, if you want to ride trails and stuff get the Hardrock, you can bunny hop and jump curbs fine with it... I'm 220lbs. and I bunny hop my Hardrock and jump off curbs all the time, it takes it fine.
My Hardrock is definitely the fastest of my 3 mountain bikes (I've got 1.5" slicks on them though).
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I rock peas on my head but don’t call me a pea head.
Bees on my head but don’t call me a bee head.
Bruce Lee’s on my head but don’t call me a Lee head.
Now please excuse me, I gots to get my tree fed.