I used the Fox ones a few years back when floater fishing. They are basically a more streamlined inline bubble float and they cast really well on a barbel rod. Could be well worth a try on your lure rod.
Ah ha ~ I thought they could be part-filled with water Michael but those FOX bolt bubbles look to be ideal.They wont cast any distance.They're feather light, and you cant load them with anything. look at the fox bolt bubbles. different sizes of inline super bubble floats. no swivels, can fill them with water. All these things will need stopping on the line somehow though.
They work just as well Mark , I save mine for in among the boulders ( ideal for the rough stuff)What about wooden casting eggs like the ones (made) i put up on here a while back (cant find the page) but i have put flys, small redgills over 100yds. with 12ft of fluro between the fly and eggs