I just did a bunch of research and tried a couple pit bikes, one of which was an auto Orion, brand new. It ran pretty well and it was sufficiently quick (and very simple to ride). The other was a Pitster Pro, which I would say was fairly similar to a Japanese or Austrian bike in quality, certainly to the drum-braked KLX 110 I considered.
I'll cover the Orion since it's more typical of a Chinese manuf.
Orion 21 Auto 125
Pros:
- electric start
- suspension stiff enough for 190lb me
- disc front brake
- available with three types of transmissions
- beefy looking chassis
- nice seating position
- engine was fairly responsive
- price : $800 cdn
Cons:
- plastic was hard and brittle
- chain and sprockets looked very cheap
- paint did not seem well bonded to metal in spots
- every sticker peeling off (my KXF isn't perfect tho)
- little details, like wonky feeling throttle
- engine did not want to run, fiddled with things, ran fine?!
- fuel petcock can't be seen
- all electrics quite exposed
- different transmissions are also in different motors
- some fasteners were actually self-tapping screws
- suspension was VERY cheap/basic
For the money I think it was better than I expected and a few little upgrades and precautions would probably sort out reliability issues. But, I was more impressed by far with the Pitser Pro. At 10hp and 145lbs it was quick enough to be fun for an adult, with a more aggressive transmission choice it would be better.
Note also that there are many variations of this bike and also the other brands - three different transmissions available, suspension upgrades either in the form of "MX" versions or upgrades. Apparently the motors in most of these bikes are from two manufacturers: Zongshen or Lifan.
In terms of quality, I've read and observed that the only ones to consider are, from best to worst:
- Pitster Pro
- SSR
- Orion
- Baja (this is a very different line)
- Others...
Please note that these are all pit bikes and other than the Pitster Pro, I wouldn't think of them as durable offroad bikes that would take any real jumping. The Pitsters are priced twice what the Orions are, though. The SSRs are in between and frankly they look like a good value in most senses, particularly the 110 A1 model. I wouldn't consider anything out of the top three.
In the end, I bought a larger bike (but not much larger) in a KLX 140. It's a little bigger than the KLX 110 physically - which many pit bike are sized against - but has a disc brake, and quite a bit more power. It's quite a bit heavier than the pit bikes but that won't bother me much as I have a large trailer and a toy hauler - your milage may vary, if you have to haul the bike by truck. Even the lightest of pit bikes is around 150lbs and can't easily be lifted, though. Here's the thing though... the KLX 140 has better quality switchgear, sprockets, suspension, etc... even compared to the Pitster Pro or its sibling, the KLX 110 - and for me this was a big part of the deciding factor... how long the components will last and how painless ownership is likely to be.
If you're looking for a smaller bike, the Honda z50s are nearly indestructable, and I've seen a few of them on kijiji in southwest Ontario. Bear in mind that at 11, I was racing a MX80 which has a power:weight ratio better than my KLX, so buying him something that will get outgrown fast is a consideration... though not everyone has immediate talent for it, either.
Hope this is helpful, best I could do.