The problem with the Atlantic is for me there is no way to add more weight so your own needs are most important It also loads the spine if that is a problem when back is sore .Also the Hammer is a Donkey calf situation so I prefer its's results over standing/can add lots of weight and is spine/lower back friendly .In a pinch can be a seated leg press. and cheaper you say.I assume you have the free plates already.Easier to move around perhaps..I am out of ideas-lol
Axtually depends also on ther machines you have like a Smith machine or squat rack you could do standin calf work in.
Donkey calf raises
This exercise creates even more tension on calf muscles {gastrocnemius} than standing.
Here’s why:
The hamstring muscles travels under the heads of gastrocnemius muscles before being inserted. in donkey raises, you bend at your hips and stimulate the hammies more.
This creates more tension in the calf muscles too due to close insertion of hamstrings. Calf muscles get tighter, and work better during donkey calf raises.
The donkey calf raises increases intensity and localization of force on the calves, and with the use of iEMG (used to record muscle activity), has shown to be more stimulating to the gastrocnemius than the traditional standing calf raise.
Through training the entire calf, the donkey calf raise places an emphasis on the gastrocnemius, the
muscle which makes up the bulk of the calf