Just about all aftermarket anti-roll bars for road cars are made to be bolt-on compatible with stock linkage geometry, so even if you do get adjustables, you should always start by matching to OEM end link lengths. Quite a few Stinger drivers report their aftermarket links would hit suspension member, so they had to change the length to avoid that. That happens because the aftermarket ones are typical fatter and have different ball joints. To me, the idea of buying adjustables only to find out you HAVE TO adjust them because they don't fit right is not particularly appealing.
Strictly speaking, adjustables are really meant to balance both ends of an anti-roll bar, such that when the car is sitting at rest loaded to "race-ready" mode, there is no torsional force acting on the bar. For street driving or even recreational track use, I've yet to find this necessary. For a road car, the load is constantly changing, depending on passenger and cargo load at any one time.
Maybe if you are into high-caliber racing, and the driver's weight - with gear - is constant, then you might consider it worthwhile to balance the bars with the car static with driver on board. Even then, that's assuming the driver is talented enough to tell the difference and optimizing that would likely result in shortened lap time.
Otherwise, it's more trouble than its worth.
