In my
experience, "solderless breadboard" is the usual term, at least
if you're talking about the things I suspect you are. Occasionally a
brand name gets used to refer to them.
That's what I've always heard them called. I know they're generally
considered terrible, but I've had lots of luck with them for low-speed
projects (especially power supplies for tube amps; I've got one that's
covered with capacitor juice from various electrolytics exploding and
has some melted-out holes resulting from diodes installed backwards but
still manages to work just fine).
They're probaly fine if used within their limitations. That is that stray
capacitance doesn't matter too much (and be warned it can matter even
when the system appears to be low-speed) and if the odd poor connection
won't cause too many problems.
That said, I don't think they save much tiem. The time taken to form
component leads to fit into one of these breadboards, or to strip a piece
of isulated wire to go in, is not much less than soldering the components
to stripboard (assuming your iron is already hot). And doing the latter
will at least eliminate poor conenctions.
-tony