The value of the 392 steroid is the capability of 20 ft/lbs in a 5.5lb self-contained rifle. Great pack rifle. The negatives are that it isn't scope friendly, has a POS trigger, and 14 pumps is a lot of effort, especially the last few. There are no quick follow-up shots.
At around $250 or so (current cost of a steroid?) you can certainly get rifles with more velocity (in .177) but you'll have to go to something like a RWS48 or better to match the power.
Then again, given your criteria (whacking birds at 30 yards), I do that with the humble little R7 (a .177 at a bit over 600fps). Hope you gave the Beeman R9 a hard look.