That's not a lot of training Rose, DAS or otherwise so that's testiment to how having your own 125 to get the miles in works.
I agree with Rose, I found riding at slow speeds much easier on my 600 but not a u-turn but I believe this is down to the riding position and I doubt you'd be taking your test on a sports bike.
There is one thing I think you are forgetting though when it comes to ladies like Kaz, Stella, Nina, Lin etc - height/strength. These girls are on tiptoes on a 125...Stella sat on my bike and if I remember rightly, didn't reach the floor at all or only just on one foot. She'd have to lean the bike quite a bit to get one foot down and I doubt has the strength to hold the bike at the angle needed. Nina told me recently she can't pick a 600 up off its side stand. There is no way even now I could push a 500/600 bike backwards so I've failed the DAS test before I even get on the bike and ride but maybe that's just me - I am the worlds weakest woman after all!
In my experience, not having both your feet firmly planted robs you of a huge amount of confidence and for me, that's what stops me managing a u-turn or pulling out of junctions smoothly and confidently. I'm scared if it does goes t*ts up, I don't have the strength to save the bike.
I'm 5:4 which is fairly average height but I have weak legs/knees, the left in particular which for many years I didn't have full use of and still don't although it's the best it's ever been now.
Just my thoughts and another perspective on things as no disrespect Rose, but you are a very tall lass and a 500 probably feels the same to you as a 125 does to nearly everyone else!
And just for a bit of balance (although it's a guy so strength is likely to be on his side) I was totally in awe of Sumo on Sat. I hope he won't mind me saying but he's not the tallest member we have on BM yet he rode a ruddy huge BMW GS1200 that I swear, at its highest was as tall as he is and he rode it like a pro!
Well done again Rose.