With the Bachmann metal wheels you essentially get what you pay for. They are typically the cheapest and it's what we use almost exclusively. They are for the most part dependable, look good, roll nicely, and add a bit of weight to your cars. However they are not the smoothest wheels out there either.
I have been contemplating changing out from Bachmann to something a little better, like the San-Val wheels. The only problem is price. To reequip our fleet would just be too much, and even a little at at time is pretty pricey. If I do ever get around to a great change over, maybe I can offset some costs by selling off the Bachmann wheels.
Like most people's experience, there are definitely a few bad apples in Bachmann wheel packs when you start getting into high numbers of wheels. The biggest issue I've experienced are the wheels being out of gauge. Thankfully you can push or pull on the wheels to fix this. One out of gauge Bachmann wheel made it's way into our
layout cab ride video. The camera car is a gondola that is rarely used. I didn't check the wheels and didn't notice a problem until after viewing the video. If you watch the video (at 2:24), you'll notice a bump when the camera car goes over a switch. The bump only happened on one switch so I thought it might be the frog. But after checking, one wheel was slightly out too far. Erg, guess we'll have to re-shoot it
If an axle is bent then there could be some really noticeable problems. With a bent axle, the car will wobble, may look a little funny, and could derail too. How many come with a bent axle, well not too many, about 4 out of 50 with bent or slightly misshapen axles has been my experience. But it's close to Greg's 10% level. Not all are beyond fixing, however if the axle is badly bent it's pretty hard to get it true. But then again, when have you seen a real trainset with perfect wheels on every car...especially on the D&RGW narrow gauge which we model
If you do go with Bachmann, the wheels fit on pretty much everything (LGB, USA, Aristo, Bachmann, Hartland, MDC). Just be sure to get the
"large" wheels and not the
"small" wheels. The small wheels are great for mine cars, but way too small for most everything else.