I have never used the Bernina machines you mention.
I agree with Janet - try them and see what you think. Imagine what you might want to do with the machine. If you want to FMQ a larger quilt, the small throat of the Berninas will be limiting.
When I went looking for my new machine, I was going to buy a Viking because I had a Viking. But when I compared the "feel" of the Viking Sapphire 875Q vs. the Horizon - for me - the Horizon won hands down. But that's me. I haven't been sorry. You'll know what feels good to you.
As to features - I heartily recommend a thread cutter, needle down position and a knee lifter. Additional features of the Horizon that I especially like are the Accufeed and the automatic plate converter - converts from zigzag sized hole in the needle plate to a single hole.
Good luck.