Not quite as good as some above but have been very impressed with both ATB and Trek warranty support......
Marin Quad rear swingarm bent, not really sure how I managed it but replaced under warranty along with the shock.
Same Marin Quad and the seat tube cracked above the bottom bracket, replaced under warranty with a complete new frameset.
Whyte E5, frame cracked around Quad mounting points, replaced under warranty with a complete new frameset.
Maverick SC Forks crack found in lower leg where the brake mount is, replaced FOC direct by Maverick in the States as no support in the UK at the time.
Whyte E5, Rear carbon swingarm separated from the important bit at the back! Replaced with a new E-120 Frameset.
Trek Remedy 9, found a crack in the seat/top tube weld, replaced by new frame with latest DRCV shock
My next bike will either be from the ATB stable or Trek
fantastic customer service..