Yes there can be a Business service on Air Nostrum's smaller jet, so if it is being sold then you will get it. Well, don't get toooo excited, have a look at the end of this post.

http://www.flyertalk.com/forum/23377318-post2.html

Yes the bins are small. I was able to get my HBO carry on bag in, since it's floppy enough but I think thicker rollaboards with rigid sides may be troublesome.