The stevens are basically the discontinued or older model the way I see it. Sort of like getting a reflex bow instead of a hoyt. You don't get cutting edge technology but you save some bucks as well.
They could easily offer the stevens guns with the accutrigger or other options, but that would up the prices. The stevens rifles are priced the way they are because they can be produced for less money and faster if they don't have to concern themselves with different options and models. Simplicity normally means a bit better price.
The stevens rifles come in two flavors, long or short action. You don't get to choose what kind of stock or finish you get. Just what caliber you want, and that is probably limited.
Some of the Savage package deals don't come with the accutrigger either. I have seen a basic 111/11 with plastic stock and cheap scope go for around $300 as well. Then again maybe they were so cheap because they were being discontinued. They still list it on the website though.
That's my thinking on it anyway. I could be wrong, it's been known to happen

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Paul