Never heard of these ones breaking before, I've broken a few of the valve cover studs on a variety of engines though. My recommendation when working on small fasteners like engine parts, the smallest tool that can get the job done helps prevent breaks. And non-torque critical fasteners, I agree with TwinTurboGTR, hand tight plus a little is fine. Always torque in stages to prevent misalignment issues, especially when installing wheels, and don't torque under load.

single use 'bolts' are generally only found in critical areas (prone to high loads and/or vibration, as in the headbolts, crank bolts/flywheel, and a couple of suspension bolts. If you ever see a torque angle specified in the instructions, that needs to be a new bolt**
Typically, the only fasteners that are recommended for regular replacing/one time use are the self-locking nuts (nylock or jetnut)

**not really, but unless you are a material science engineer and willing to run the calculations to determine the new torque angle for a previously stretched/yielded bolt, it's safer to just replace it.

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Olympic Peninsula, WA, USA
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2005 Mini Cooper 100k, British Racing Green/Silver-Black
04/2002 4.6is 140k, Silver/Black-Alcantara *FOR SALE*
1989 325iX 270k, Diamond Black/Black
1984 318i 370k *SOLD* (First Bimmer)
Honorable Mentions: '71 2002, '87 325, '90 325ic, '92 525it, '93 325i, '94 530i