(3/1/03 2:37 am)
I used 1 to test out the part when they were around average level of 9 or 10.
They dont have a great AC and even with +10/+5 they will be still need fairly good rolls to hit depending on the party level, but im guessing most of your party have a fairly good AC by now, if you are consider using them. In the end invis stalker may just have a better chance of getting way than most creatures.
With good listen checks the party may hear them coming depending on how well you roll for Invis Stalkers Move Silently.
Also with if members of the party have Blindfighting, that will also give them a better chance of hitting.
My mage/thief uses glitterdust spell to outline invis creature, even if the the Invis stalkers make thier save, they still can be seen.
I guess it all comes down to what spells the party has, trueseeing, see invis. And what level they are, you haven't mentioned anything about the party to really make it easy to answer your question.
Hope this helps