Was in exactly the same situation as you, trying to decide which one to go with. Since ours will be mainly for field and plinking, and only occasionally on the bench, or a varmint setup, went with the American, 2 of them.
Actually went with the 453, which is the version with a single set trigger, and a Nikon Monarch 4-16x42 side focus mildot. The other is in the process (likely) of getting a Sightron SII Big Sky 4.5-14x44 mildot. Both of these are relatively compact scopes, and decent quality...
The 452 Varmint and American has been discontinued, and replaced with the 455. There are still some in the supply chain.
Apparently the 453 Varmint and American are still being produced.