The first question to ask is what do you want it for. I wouldn't get the Art Deco because of materials, but the other three have different purposes.
I've only used the Icicles #14, and it's a good plug for active play and prostate stimulation, but the handle gets in the way if you try to sit down.
I don't have the Moon Shine, but I have the very similar Sexy Spades Small, and it slides in easily and is comfortable, but doesn't have as much prostate stimulation. The large has much more prostate stim, but is a lot of plug. The medium is probably somewhere in-between.
Don't know about the Frosted P-spot. I do have the Severin Medium and it gives good stimulation.