Neither of these are that soft, at least not in the same way as Domains/TCs are soft. Not that they are bad skis but they aren't as buttery as others. The ARV is the softest of tha Armada Line. The butteriest all out park ski is probably the Domain. I didn't like them particularly but a lot of people love them.
I can't speak for the halo, but I own the 12 and 13 Thalls and have ridden the current TC's and yes they are a 'different' type of soft; but buttering is much more fun/better/easier on the thalls imo. TC's are still a great ski, I just preferred the armadas. The ARV is the softest armada however I have not yet had the opportunity to ride them