I have used an FT-60 HT and an Elk Satellite antenna and have had relatively good luck on both AO27 and SO-50.
It's important to be sure that you have the satellite position correct. Most of the birds are only at a good angle for communications for around 7-8 minutes, so you have to be quick and brief. I've also discovered that the angle at which the satellite antenna (Elk) is held makes a big difference (polarity). You just have to experiment until you get the loudest signal then track it across the sky.

The higher the pass in the sky the better your success. Those that are at the horizon will be very difficult to make contact unless you're using something special and have some altitude yourself.