In terms of looks:
The Legacy version is much more toy-like in appearance, and it hits you almost immediately. The wheels on the leading and trailing trucks have none of the detail seen on the Premier version. The trucks themselves have a much lower degree of detail. The driving wheels are not chemically dyed to give them a darker appearance. the engine is completely missing the bell - poor oversight? The detail along the top and front is less. And the tender trucks are missing the little chains that give the MTH version from 2008 a much more real appearance. The coal load, while real on the Legacy version, is very uniform in a molded shape, making it look a lot less real than that on the Premier tender. Even the tool box on the rear tender lid is not present. I would say the only item where Lionel may have been more prototypical (and I'm no expert on whether this is the case) is the skid tread along the sides of the locomotive. The Lionel loco has actual perforations in the metal whereas, the MTH version has a textured finish. Also, Lionel offers a feature as standard fare that I don't think I've seen on many Premier locomotives - but that I really dig - the variable glowing ash pan under the cab. Legacy has the better detailed cab interior but more in terms of painted gauges than in terms of more detail.
Winner: MTH, hands down.
In terms of sounds:
- Both have a quillable whistle, but Legacy is clearly easier to operate. In terms of the whistle sound itself, this is probably a matter of preference so I won't comment Other than to say neither offers a smooth up/down the scale sound.
- In terms of crew talk, etc., I prefer the Premier random chatter over the need to launch the same basic sounds that are on all VL and Legacy engines I own.
- Engine random sounds - Legacy has a bunch of creaking and groaning sounds that give this thing a real feel. I don't know that MTH has much of this, although it does automatically launch a clickety-clack sound when the locomotive stays at a constant speed over 30 SMPH.
Winner: not sure there is a clear cut winner, but I prefer Legacy.
Engine Performance:
Maybe not fair to compare after operating the Legacy locomotive for one session, but as usual, Legacy is as smooth as silk. Great very low speed operation. No unwarranted fault messages like often occur with DCS. Having said that, the Premier is very smooth from 3 SMPH up and shows no performance issues whatsoever after having been run for approximately 120 scale miles so far. Smoke, while not nearly as good as MTH (I think MTH is always the clear cut winner on smoke units), is not anemic and actually better than I expected. I've come to expect little more than a wisp from Lionel locomotives, but this thing is a very decent smoker. Bell sounds are neutral (don't think one is better than the other - although, with the lack of a bell on the Legacy loco, it makes for a curious experience hearing the ghost bell).
Winner : Legacy (due to smooth operation).
Overall: MTH wins easily in the looks department. It just looks a lot more realistic than the Legacy version overall. Lionel wins in the department that matters most when you have young children as I do - smooth and predictable operation. Having said that, the Legacy unit has 7 years of possible innovation and advancement advantage over MTH's Premier engine that came out in 2008 - yet it seems like the MTH locomotive has done a better job of providing a more prototypical and highly detailed locomotive that we've come to expect today. And the Legacy set is 50% more costly than the Premier set was. Even considering inflation, aluminum cars (also less detailed, but beauties!) etc., I would have expected better detailing for the price paid for the Legacy set - but overall happy with it. So, don't know that there's a clear-cut winner here as each has it's pros and cons, but if I'm being honest, I am somewhat disappointed with the level of detail or lack of it on the Legacy Pocahontas set. Will post some compare photos a little later (Pocahontas photos are first, Powhatan follow).
Hope this was helpful.
Peter