Colin,

> The after_update trigger posts event "STOCK" || stock_id.

Thanks - that is similar to what I intend to use
In terms of scale of operations, how may records do you have in the
table(s) of interest? About how may clients are online at any given
time? How many "interested" clients do you expect for a given STOCK
(max/min values will help me to scale my application).
Have you had firewall issues? I believe you can configure Fb to use a
given port for Remote Events.
A general question about using this with ADO.NET. Does each client
maintain a persistent connection to the Db in order to receive remote
event notification? - I realize there is a synchronous and
asynchronous mode - any recommendations or pointers? Are there overall
performance issues that I need to consider when using one mode vs. the
other?