Many top-rated U-locks are quite expensive, and the OnGuard Brute STD 5001 is no exception. It performs well in theft tests, winning a bike-lock test conducted by Maxim magazine and scoring very well in an older test by Slate.com. In these tests, reviewers are unable to saw through the 16.8 mm steel shackle, and the lock doesn't budge in a direct assault with a hammer. It does eventually succumb to a tester with an angle grinder, but most bike thieves don't carry power tools with them. The OnGuard Brute STD 5001 U-lock has a long shackle, so it's a good choice for beefy bike frames or for securing both the frame and rear wheel. However, reviewers think the large size makes it unwieldy to carry, and the included mounting bracket doesn't seem sturdy enough to support the 4.3-pound Brute STD 5001. If you live in a low-crime area and want a lighter lock, the OnGuard Bulldog Mini 5013TC U-lock (*Est. $30) weighs just 2 pounds.
The best comparative review of the OnGuard Brute STD 5001 comes from Slate.com, which pits the U-lock against several other bike locks in a head-to-head test. While the test is several years old, most of the locks are still on the market. The New York Times also highlights the OnGuard Brute STD lock in a shorter review. Over 30 reviews at Amazon.com average out to a solid, high rating with the chief complaint being inadequate mounting hardware, and nearly every user review at BikeSomewhere.com is positive.
The OnGuard Brute STD 5001 performs very well on the security portion of this detailed test from Slate.com. Scott Elder is unable to bust the U-lock with a hammer or hacksaw, but he thinks the mounting bracket is too flimsy for the 4.3-pound lock.
Review: Avoiding the Bicycle Thief, Scott Elder, April 18, 2006
2. Maxim magazine
In Maxim's test, the OnGuard Brute STD 5001 comes out on top -- besting two other locks, even though all three were busted with an angle grinder.
Review: The Great Lock-Off, Steve Mazzucchi, May 2009
More than 30 owners of the OnGuard Brute 5001 STD U-Lock give it an average of 4 out of 5 stars. One user found that the lock had rusted in the rain, and another said that it wouldn't open in extreme cold. There are also some remarks about the mounting hardware breaking or allowing the lock to slip out. Still, the majority of reviews on this site are positive, saying that the OnGuard Brute 5001 is very strong, reliable, and if anything, possibly overkill.
Review: OnGuard Brute 5001 STD Bike U-Lock, Contributors to Amazon.com
Only one out of six owners gives the OnGuard Brute STD lock a less than stellar review, stating that the mounting bracket doesn't do its job of holding the lock in place on a bike. The rest of the reviews make note of how the lock itself is, while heavy, very tough.
Review: OnGuard Brute STD 5001 Bike U-Lock with Mounting Bracket, Contributors to BikeSomewhere.com
5. The New York Times
Brad Quartuccio, editor of Urban Velo, highlights the "industry-leading" $5,000 anti-theft warranty that comes with the OnGuard Brute STD 5001. He also says it can effectively lock wheels and a bike frame, but its size makes it hard to carry.
Review: Physical Culture -- Gear Test, Locks, Stephen Krcmar, Aug. 2, 2007