the Hornby tender drive unit shown [the 'Henry' drive unit] is a very capable piece of kit.....my son conned me into buying a Henry a couple of years back, and surprisingly it performs very well, being QUIET, smooth and powerful enough for most needs....considering it is essentially a ''toy?''
[It would seem somebody at Hornby has been influenced by old-school railway modellers who strongly advocated [like CJ Freezer?]...that engines for younger POTENTIAL enthusiasts should be excellent, reliable performers first and foremost....nothing erks a child towards disinterest more than having to continually prod an engine into life]
It ought to be easy to convert to DCC.......why not ask Hornby themselves?..if I recall correctly, the tender doesn't pick up traction current anyways? [or am I wrong there? I haven't bothered to dig out Henry to check.
at the prices quoted,one cannot go wrong..I suspect a Fleischmann item would attract seriously Fleischmann prices..or be of an age when code 75 track was something only those 'orrible britishers used?
the ringfield, or pancake motor and transmission design is old, yet SOUND technology...advocated first by model engineers more than 50 years ago.
[check out comments by Iain Rice in his book on locomotive chassis construction.]
oh...and as an additional reference, one Steve Rabone [of toddler article fame] hasbuilt a number of tender locos in S gauge...using tender drive units [principally the old Airfix unit]..... with ingenious adaptions for re-gauging.
perhaps this is a possibility, seeing as Russian railways use a broader gauge than 't'uthers?
go for it and play around a bit