With the 4018 and its variants you get a large oval with two sets of points which give you a passing loop/run-around and also provides an area where a station can be sited.
With the RC steam sets, you get a figure of eight which includes a cross-over, one set of points to form a siding and a buffer stop.
Of the two, the 4018 layout is the one I prefer and with the addition of another set of points, a curve and a few straights and a set of buffers you can add a siding which adds further to the value of the layout. Another alternative is to get two extra sets of points and some curves and make an S across the oval. As well as points, straights and curves, you'll also need the little track extenders.
If, btw, you see RC sets being sold with just an oval, then unless the set is the 4010 goods loco, the track is incomplete.
