I have a few of them 2in1 and shapers in varies colours given to me when they visited RBF a few months ago.
I caught nowt on them, swapping to maggot i did catch. I was on the speci lake trying to catch the big roach.
Others used them on the match lakes and caught F1s.
The young F1s will chase and eat anything remotely looking like a pellet so that doesn't say much.