Seaward has a smooth, subtly sweet flavor. Grapefruit definitely presents as the leading note in both smell and taste, while the rest of the flavors offer a soft background of of "marine/coastal" touches. It serves very well mixed simply with sparkling water or tonic water, to your preference.
I'm not quite sure why it's listed as a gin alternative, as I would describe it more as a citrus-forward spirit, with very little of the herbaceous notes that Pentire's first offering, Adrift, carried. If you previously tried Adrift and weren't particularly fond of it, I would still recommend recommend giving Seaward a try, as I find its flavors much more universally palatable and engaging.