When you place the Buzzz and Stalker in the bag, next to one another do they lovingly nestle or do they scratch each other's hotstamp off?
In the words of Rodney King? Can't we all get along?
The Buzzz and Stalker may be similar in flight (of course they are, they were designed to be) but not as similar as a stack of Buzzz's are to each other. Many players carry multiple Buzzz's in the bag without anguish.
In my hands the Buzzz is a great controlled midrange whose best skill is flying dead nuts straight. The Stalker is a great controlled fairway driver whose best skill is flying dead nuts straight. With less effort but the same angle the Stalker flies just like the Buzzz but a bit longer, so I use it for shots where that is the result I am looking for. I also noticed that the Stalker seems to fight the wind better than a Buzzz. No real surprise as drivers tend to fight wind better than mids.
All discs have their comfort range. Within that comfort range your accuracy is much better than when you push to the outer limits or beyond that comfort range. So don't push the limits of your Buzzz, find something that does it naturally. An easy 7 iron is more controllable than an overextended 8 iron.
Tweener discs, by their nature get less use than discs which are basic staples. And every tweener range brings up a judgment call. If you don't know whether to throw the putter or mid, throw the mid unless going too long is the primary danger. If you don't know whether to throw the mid or the driver, throw the driver unless going too long is the primary danger.
There is always the temptation to pull tweener discs out of the bag. You can look at every drive off the tee and decide if you need it on a given course. But you can't predict when the winds change or when an upshot might land in the tweener range. We carry back-ups for the same reason we carry tweeners. Life and frisbee are not predictable.
There are a number of discs which are controllable fairway drivers, including Stalkers, TeeBirds and evidently Power Drivers (never actually saw a PD but have heard they are TeeBirdish). Comparing similar models is like judging a beauty contest. You might like the blond. I might like her sister. It is hard to be wrong but easy to argue about.