I buy as a hobby, and don't know if the Hercules series will be worth more than spot. However, I really like the topic and have a small case to add all of the series (I am getting the proofs).
IMO, the hydra looks fantastic and the lion actually looks better in person. I also got three 5 ounce (2 copper and 1 silver) so I can display both sides of the coin.
These "series" are turning out to be some of my favorite to collect. Partly because I just looked at the promotional card they sent to see then the next in the series comes out. Fun, and really pretty inexpensive compared to buying tubes of ASE.
I am also doing the zombucks and really love putting the coin it replicates next to each one in the set.