As it happens mate yes I did get the Marklin set, I've just not had chance to really do a lot with it yet - lots going on in the 'real world' lol!
However initial thoughts are that it is incredibly well made (as you'd expect from a german train maker), however at the same time the model is not highly detailed, but I figure this is because it is aimed squarely at the younger train interest.
But having said that they haven't cut corners, the track which looked like the trackmaster type track (i.e. all plastic with moulded bed/sleepers etc...) is in fact real HO track. It does have the plastic moulding for the bed/sleepers, but the rails are real metal rails and I suspect totally compatible with the normal Marklin HO sets. All it would take is an additional piece of track with appropriate connections that could be electrified and you could run a standard electric HO loco on it.
Going back to the train itself, the wheel spacing is accurately HO gauge, so it would not run well on Tomy track, but again it would allow the train to run on a real HO gauge layout, so again a 'growth path'.
As I probably mentioned before the train is a 5 car unit and although battery powered it takes 4 x batteries so should offer good performance. The coupling between the carriages is magnetic, so no fiddling about and you get quite close/realistic coupling. The other nice addition is that it is out of the box remote controlled, with a remote that gives you multiple speeds both forward and backward, with an emergency 'stop' button. You also get 3 buttons for sound effects and a fourth button to turn on the train headlights.
All in all I think it is a stunning bargain for only ~ £40 brand new, it even includes a set of batteries for both the train and the remote