Making the runner lose a click sounds great for setting up a scoring window, but Load Testing requires a click to play itself so in effect you trade a click for a click. That's not to say that's not useful occasionally. The most prominent scenario I can think of (I fear I have a really poor imagination) is that of a 4/2 agenda. You install it on click 1, advance it on click 2, do a Load Testing on click 3. And then you need to have ice that's good enough to keep the runner out if they have 3 clicks to spend but not if they have 4 clicks. That means bioroids, specifically:

• Enforcer 1.0, 4 subs, 1 strength. Works great if the runner doesn't have a sentry, at least 3 subs scare the runner and it's rezzed (since it doesn't stop a run it needs to scare the runner so they don't initiate a run).
• Fairchild 3.0, 3 subs, 5 strength, to break, all or nothing. FC3 is strong enough on its own that it's worthwhile to install even if you aren't Load Testing.
• Heimdall 1.0, 3 subs, 6 strength. The runner could get through by taking a brain damage.
• Vikram 1.0, 3 subs, 5 strength. Same problems as Enforcer 1.0.

The other bioroids cannot be clicked through with 3 clicks (because they require a pair of clicks to break up to 2 subs or because they have only 1 or 2 subs).

Of course you can always stack bioroids, e.g. Eli 1.0 behind a Fairchild 2.0 to get the same effect.

Still, this feels rather brittle. How often are you going to be able to actually use Load Testing without the runner having breakers installed? I suspect you can go through most tournaments without this trick ever working.

Are there other options? Defensively it's a decent Hyperdriver counter (doesn't stop the runner getting 2 extra clicks but it's likely they were counting on getting 3 extra clicks and this message up their plan) if all you need is to delay the super turn slightly.

I'm pretty much drawing a blank here what else you can use it for.