I don't disagree Adrian, but satisfaction is relative to what your main areas of interest are, together with the amount of skill & time you have available. You have to take account of the fact that not everyone is into building rolling stock, some people just like running trains or building scenery - and gain their satisfaction that way. It doesn't really matter that the wagons are not 100% accurate as long as they 'look right' in the overall scene. And in terms of accuracy, where do you draw the line? You could quite literally go insane attempting to take prototypical accuracy to the nth degree: Do they have the correct number of springs? Are they working springs? Are they fitted with a vacuum reservoir? Do they have working vacuum brakes fitted? Are they built from steel and lined with real glass? Do they have cow milk inside them? It is all relative. A metal kit would undoubtedly be more visually accurate, but to what degree does this represent prototypical accuracy compared to the full size prototype? As an example, take Ace Trains coarse-scale tinplate BR Mk1 coaches. Visually, these are inaccurate compared to finescale kit built ones. However, the Ace Trains coaches feature prototypically sprung commonwealth bogies. Does that make them more or less accurate than a kit build bogie that is visually more accurate, but does not feature working springs? I don't know, I guess it depends where your priorities are. Notwithstanding that, if your kit-building skills are limited, you're not going to be very satisfied with a part-built / shoddily made milk tanker that you lashed up yourself. And I doubt many new converts from the smaller gauges to O Gauge, who may be inexperienced kit builders, are going to want to start with a £40+ kit that they are likely to bodge. The availability of new RTR O Gauge models is what is drawing people into the gauge. I don't see these as replacing kits, they are complimentary to them. In due course, purchasers may want more detailed and visually accurate rolling stock, so turn to kit building these. However, the initial momentum may be from the purchase of say an RTR loco, then some rolling stock just to get things running. I don't see that as a bad thing. On the contrary it is to be encouraged.