I feed my adult bantams pellets. Like anything else new, if they have never seen / eaten pellets they may not want to eat them at first, I usually mix crumbles with the pellets for the first couple of weeks when switching them over.
I just switched over to Texas Natural non GMO pellets with my flock. They were curious at first and pecked a bit. Hardly interested the first week or two. Week 3 I noticed more of it being consumed more quickly and today I noticed my buff orp Bantam eating it when she used to stick to the crumbles I offer as a second choice. Texas Natural does a pullet grower crumble, but I don't think they do a layer crumble.
I only have 8 birds, so at first I took a brick and crumbled up a little of it in a bucket for them at first so they could get the hang of it better. They seem to have gotten the hang of it now I was hoping little Bantam would get the hang so I could just stick to one feed type for now. So far so good. I'll keep offering crumbles for the next few weeks and hopefully change her over gradually.