for every recommendation on a livestock route you'll read based on a poster's positive experience, there's at least another who had nothing happen, and ended up w/ an extra/another critter. sometimes one they only bought because of it's hoped for utility. whatever you do get (if you decide to go that route), just be aware you may have to remove it in the future. (anything that finds a stinging aip palatable is likely to also find more mildly stinging polyps the same).
camel backs,peppermints, cleaners, and most other shrimp will at the least pester corals for any food that lands on them at feeding time. the only place i'd personally put any shrimp in any future setup would be the sump, as egg producers for the DT, heh.
will they be a major issue in every tank ? no.
no other aquarist's experience w/ a particular individual fish or invert is guaranteed to predict your own
i've sold plenty of copperbands, racoons, shrimp to folks for aip predation. i'd say the results were a 50/50 split. (based on customer's feedback).
if someone else had a 90% success rate-it doesn't mean that either of us can conclude the other's wrong

(and i'm not saying that anyone in this thread is wrong)
one aspect of aip reproduction that hasn't been touched on here yet, and is just as important, is making sure you limit the food available for the aiptasias to begin with. they can obtain nutrients from food particles, as well as directly from the water column, and they can reproduce incredibly fast.
absolutely pristine water quality and feeding management goes a looong way towards eliminating them, and a large or growing population is a sure sign of over feeding of some sort, on a regular basis

one flake or pellet that hits an aip can be considered worth dozens more in a very short time.
i've placed lr w/ aiptasias (as most have, unwittingly or not) into every tank i've ever owned over the yrs-never have they survived long term-they're usually all gone w/in 6 months after setup. i've never been able to understand how they get to nuisance proportions in aquarist's tanks to begin with, when it's so relatively easy to starve 'em into oblivion from the get go.
a mix of the methods proposed in this thread is probably the best overall approach for most folks.
fwiw
