Well Madman you are to be congratulated on raising this topic: to live steam or not.  To gain a feeling for playing with live steam search for on line videos of the Great Southern Steam Up (on this weekend 8-9 November at a hall in Emerald, Victoria - the terminus of the NG Puffing Billy heritage railway. 
For garden railroaders ease of use is important. First years ago it was clockwork (wind up) powered large scale models in O gauge, then along came LGB low voltage electric resilient plastic models in 1.22 scale on 45mm brass track! at a reasonable cost many people could afford, and now these models can be battery powered, too. Most importantly for enjoyment of ‘live steam’ is the provision of a ‘steaming bay”, fire proof and at about waist height.
Now every thing happens in Victoria this week: today there is the Melbourne Cup, the horse race that stops the Australian nation for a few minutes. The TV room has to be prepared, tasty nibbles and sparkling wine laid on, so as to enjoy the spectacle of rain soaked Flemington race goers attending the event. I will have the best race track view and informative commentary at a dry leisure venue!