I received the Tangent O scale email blog a few minutes ago... I believe they will only be making brass in O scale ...From the email.
"Why a Brass model? Our decision to provide a hand-crafted model constructed from brass - as our first foray into O scale - is simple. We are testing the waters for this market, both in style of product offered (painted and RTR) as well as what sort of volume the market will support. We understand that some customers might prefer a plastic-based model, however that is very unlikely from us in O scale. New tooling for O Scale cars costs well into the $6 figures, and a majority of our HO scale tooling has multiple variations in parts and bodies which effectively doubles or triples the plastic tooling cost. We do not and will not offer simple "one size fits all" models. O Scale Brass can yield beautiful results, as our first model has demonstrated."
I am on the fence buying one or not...Will be curious to hear the reviews when they start being received. Maybe that will help me decide to buy one.