Vango all the way, just bought a Vango Sapera II,
they don't make this model anymore but you can still get hold of them take a look on the net
it has been replaced with the "Kela" in my opinion this is not as good as the Sapera II
The Kela is smaller than the Sapera II, also all new Vango Airbeams don't come with an inner bedroom they are an optional extra
but they do come with the Sapera
As for the rail height, Vangos come in three different heights Low, Standard, and Tall
there is plenty of info on Youtube just key in Vango Airbeam Reviews
Hope this helps
Vinvan