Shimano Acera

Pros: Looks better than it used to
Cons: Still an el cheapo derailuer.

What makes a good derailuer a good derailuer? Is it price, performance, or durability. Of course it is a mixture of all these things. So I think it is a worthy use of time to forgo the typical evaluations of Shimanos top end offerings, and look to the...

Pros: Cheap
Cons: Cheap

Simano makes eight levels of mountain bike components. The high end, of course, is for racers and hardcore folk who really need decent performance. The low end is for unsuspecting buyers in department stores or looking for low end shop bikes. These...

Pros: Great Derailleur, Looks good and shifts very well and comes with a great price!
Cons: Still a tad heavy but hey it works good!

I purchased this derailleur as a replacement for my stock altus which came with my mountain bike that I had bought. This derailleur is better in many ways than the Altus. Unlike the altus, this derailleur shifts great and looks even better.

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Pros: Low Cost, Cheep Upgrade for all bikes not just namebrand ones.
Cons: Some issues on rear 4th-5th gear.

I ride daily, and both my bike and my friends have cheeper deraillers on the rear. He has SIS front and I have a C050 SIS on my front. He has Shimano Acera on the rear and I have a Shimano C050 on the rear.

My rear gears tend to click a...

Pros: Worked great for awhile
Cons: Must be poor quality

I have a Trek 4500 with a Shimano Acera. I ride 12 mi three times a week on dirt and gravel. After less than a year, the Acera won't down shift correctly. It upshifts accurately. The worst case is when you up shift from 7 to 4 in one push then try to down shift from there. It won't go from 4 to 5. After two clicks it will go to 6. Then one more click to 7.
I've tried to adjust every screw on it with no avail.