Well Rod, I'll be honest; I sent mine back to Lionel for the "tender vent" smoke feature working inconsistently as far as the smoke function working. When I trigger that feature, the sound portion of the feature ALWAYS works, but not the smoke. The sheet Lionel returned with the engine stated that every time they triggered this function, it always works over "hours of running". I run my layout with Legacy Cab2 powered by two Powerhouse bricks running through a TPC300.
Once it was returned to me, it took 13 tries before the smoke actually emitted from the overflow vents. I found that the smoke function is very susceptible to miniscus' forming in the smoke exit tubes which blocks output. This is with the "warranty required" Lionel Premium fluid being used. In short, the tender smoke feature is problematic on my unit. I don't plan on sending it back to Lionel as the inner shipping foam container is already under "duress" after this last trip + I'm not sure it will actually be fixed correctly at Lionel as after seeing results from this return.
On the plus side, the sounds are awesome along with the Legacy speed control and 4 chuffs per revolution. Smoke from the stack/whistle/and pop-offs works well. I also liked the blackened side rods; my personal opinion is they could have left off the white wheel sidewall trim.
One item I feel Lionel dropped the ball on is not putting the two center rail pickups on the tender assembly further apart to allow drop-out free sound crossing large turnouts like my Atlas"O" 7.5 degree units. I would have deleted the Legacy IR sensor and put the second roller in that area. A "VisionLine' engine shouldn't need a battery back-up or a $40.00 capacitor installation to allow steady sound output over crossings and turnouts IMO.
As delivered, mine (and some others documented here on the Forum) arrived from manufacture with the tender drawbar not being bent "level"; this allowed the tongue on the engine drawbar to hit the center rail at times and cause a short, especially while backing-up. bending the drawbar to a horizontal position solved that issue.
In summation; smoke features can be problematic; the Legacy control/4 chuffs per revolution/and Legacy loco-tender Railsounds combination are the positives for me over my CCII unit