Hi, I have four roundhouse locos two kit built , i find the 040s are far better on uneven track, the silver lady having a slightly longer wheelbase has to go slower around tight curves. If you choose use a manual loco i find the 040s slightly better aswell, if they stop on a uphill section they just build up steam and are of again fairly quickly and controlled where as the silver lady may need some encouragment, if your track is nice and level though the silver lady goes round so slowly pulling a heavy load. Havnt got and photos or videos of silver lady around my friends track which is extremly level, if you go on youtube and look for encore1332 you will see my trains around my rather uneven track.
of course if you get a lady ann with rc you wont get any of my issues