I got the recently released DCC UP light mikado. It quickly developed a major mechanical problem…bucked a bit, stopped, etc. I returned it to MBKlein…thought they were going to send me another but they fixed the problem and sent it again to me. It’s run ok since. It does have traction tires…some people don’t like them. It is more sensitive to sound interruptions than my other three locos, at certain spots in the track it must be losing contact very briefly (too briefly to see headlight flicker) and the sound skips. I also have a several (5?) year old BLI Mountain that does not do that (both have 4 driver wheels for pickup). I purchased the Mountain very slightly used this year at my LHS and the fixup guy said they all had an issue when built that he corrected (something about the driving wheels, I recall). I believe the sound system in my newer mikado is different from the earlier Mountain. Don’t know if the Mountains you are looking at are an updated series.
I would buy each again, not arguing they are ideal, but I’m fairly pleased with both. They are different enough that I enjoy each; e.g., the Mountain is bigger, heaftier, longer so the two engines provide a dofferent look.
I plan to acquire some UP Athearn Genesis 4-8-4 and Challenger engines when released in 2013, so I’ll have a brand comparison with steamers. I have a Genesis GP9 that I am vrey pleased with.
Here are some earlier threads:
http://cs.trains.com/mrr/f/88/t/208846.aspx