Jan,
I was quoting one of our pioneer LC's here in NYC, who is very, very wise.  It
has been her experience that adoptive nursing moms develop better milk
supplies using the Lact Aid than the SNS.  In the Lact-Aid, the milk container
sits upright, with the tube entering from the top, so milk only flows when the
baby sucks, encouraging effective suckling.  THe SNS milk container is upside
down, with the tubes coming out of the bottom, so gravity pushes milk down the
tubes, leading to a more passive feed.  Of course there are valves in tube
assembly to decrease dripping, but it does still occur.  Each device has its'
pro's and con's, so it behooves us to know these and recommend the correct
device for the situation. I personally use SNS for slow gaining babies to give
them more immediate calories while we work on the suck.  For kids with really
ineffective, unsustained suckling, I prefer a syringe and tube, as the
controlled bolus one can deliver triggers swallowing, which leads into another
burst of suckling.  My point is that our good experience with an one brand of
materials in one situation should not lead us to blindly recommend that brand
when another would better meet the client's needs.
Catherine Watson Genna, IBCLC