I've been driving beds off and on for years. If you have a soft bottom they should do fine. The harder the bottom the more likely they will float or pull out from current.
If you haven't built your driver yet then I would recommend a 3' aluminum driver head about 2' long reduced down with a bushing to 1". We use 1" aluminum conduit in a 8 or 10' stick for our handles. We also either weld on a keeper ring for a rope or the easier more helpful method is to put a pool noodle on the handle down by the driver head. This will allow you to test it out in shallow water and make sure it floats so when it gets dropped in deep water it will not be lost. " Past Experience!! Ha"
Depending on how deep you are planning on driving your bed you can add a coupling to end of handle and make a extension.
My experience in the past is that these beds last twice as long as the built beds.
Hope this helps...