Hi Nick
Having not done any real barbel fishing I can't really comment on their suitability with the kind of bites you'll get...
However....
I do a lot of feeder fishing with a baitrunner and I wouldn't be without it now. Admittedly, occasionally I will actually engage the lever for its proper purpose (a screaming bite) because I want a pee or a snooze. However, I also find myself using the little lever a great deal for other reasons - e.g. tackling up when I want to pull line off the reel, its much more controlled than just opening the bail arm... in fact, any other task other than casting where you need to open the bail arm is more controllable using the baitrunner. So for example, letting out a couple of extra inches of line to a finicky chub bite... or letting our line to balance a quiver tip in a flow. What I've found is that once I got used to having the option of the baitrunner, i'd use if for all sorts of things I hadn't really considered... and then when I went back to feeder fishing with a regular fixed spool reel, I found i kept reaching for that little lever!
So my reccomendation would be, use a baitrunner.... possibly not for what it's designed though! I'm sure more barbel-orientated folks on here will have opinions!