I've used both too. One thing to watch out for. Bachmann has both "G Scale Wheels" also labelled as "Standard Metal Wheel Sets", part #92421 which are 31mm dia. and "1:20.3 Finescale 32.5 MM Wheel Sets", #88071. In my experience, the finescale wheels seem better made, and are a bit heavier but can drag against the molded on brakes of LGB two axle wagons because of their slightly bigger diameter. I was disappointed with the QC on the standard wheels. Two out of the 4 "Standard" wheel sets in a pack I bought to check them out had noticeable wobble due to poorly aligned center holes. One was so bad it really wasn't usable. I ended up using the finescale wheels I bought on a 4 axle wagon where clearance wasn't an issue. They work great in this application and I haven't had any coupler problems caused by the slightly bigger diameter. But, I've gone back buying only LGB metal wheel sets when I need to replace some plastic wheels. They cost around twice as much as the Bachmann wheels but their quality is consistent.
Edit added: I will probably try Bachmann's smaller 24.5 mm diameter wheel sets when I get around to replacing the wheels on my LGB log dis-connects. I've got link and pin couplers on these so coupler height is not really an issue.