I've sat the RAF tests at OASC twice.
I went first time for Flying & Sixth Form Scholarship back in 1997. Unfortuneatly, I failed... if I recall right, the 'slalom' test. Red spots trickling down the screen. White spot, to be moved over the top of as many of said red spots as possible, using a joystick that moves the white spot left and right... It's been a while...
Anyhow, I was given the Flying Scholarship to improve my aptitude and asked to return. I did the Flying Scholarship at Cumbria Aero Club on C152s, soloed after 6:25 hours and was rated 'Above Average' on the Final Progress Check... Needless to say, that counted for nothing on my return to OASC when I buggered the test up for the second and final time. Two attempts and you're out.
The RAF tests are loaded towards completion of a Fast Jet OCU. If you pass them; statistically you're likely to get through the aforementioned course. FAA tests are the same. The AAC, which I was told that I had passed is loaded slightly different. AAC only use helicopters and Islanders, you see. I'm no expert, but I'd imagine that the tests are loaded differently. More of the 'pat your head, rub your stomach' kind of thing, as opposed to quick reactions? Like, I said, I'm no expert.
Interestingly, I sat the CTC tests back in 2006 when there was a decent cadet scheme, that was directly affiliated with Easyjet employment and not this Flexicrew rubbish...
Anyway, I found these harder than the RAF ones, as did a lot of people, who had done both. Needless to say, I didn't pass those either!
Prior, to going to CTC I bought the Cockpitweb mock tests, within a day I was getting top scores.
My opinion is that they're a load of nonsense and only a rudimentary indicator of ability. A friend of mine has just got through the Jet2 selection. Recently, they've decided to use COMPASS. Several experienced pilots, (some TRE's/TRI's) failed this test - to give you a flavour of how relevant these tests are to 'real world' ability.
I understand your concerns, there are a lot of airlines using these tests and now it's just another hoop to get through, which in my opinion doesn't bear a great deal of relation to one's ability as a pilot. That's why we have Skills Tests and regular Simulator Checks...
Reinvention of the wheel in my view.
But just an opinion!