I didn't get blood tests done because he said it wasn't necessary, that he's in good health. I assume though it's also arthritis related. I think I might make one of those flat perches, since the ones we sell at work are more conure sized.
Please let me go bash my head against a wall first...
Forgive me if I do not agree with your vet, but a bird with known health problems (falling while sleeping is not normal) and he doesn't think blood tests are required? A bird can appear perfectly healthy, but blood tests can say otherwise.
He climbs just fine but I guess it seems his feet don't "lock" like birds so when they sleep? Normally he's fine, it's only when he's sleeping that he ever falls.
My cherry headed conure (RIP) was the same exact way. He fell less often when he slept on rope perches vs smooth wooden perches. I felt bad for him because when I got him, he had all smooth wooden perches all at the same level and grouped in a manner that if he did fall, he had problems climbing back up. I could understand in the sense if the perches were strategically placed that if he did fall, he'd fall onto another perch, but this wasn't so.
Unlike normal birds, my cherry head slept with his head forward, and, over time, his head would slowly lower... sometimes even to the point that his head was lower than his feet. (scary to watch a bird sleep in this manner) If he woke up, he'd sit normally, but it was only when he was sleeping that he became "top heavy". At one point, he had a box he could sleep in, but had to remove it, thanks to his little cockatiel friend. He also had a platform perch (wire one) which he didn't take much interest in most of the time.
His blood tests were not normal, but they weren't quite abnormal either. I had put him on the Roudybush Renal Care diet, and he actually did better on this diet than any other I had put him on (although never tried Harrison's). Truth be told, his uric acid levels were not high enough to indicate kidney failure (they were on the high range of normal, if I recall right), but he definitely 'improved' on that diet. (droppings were less watery and more firm - not normal, but assuredly improved) He also did well on Metacam.
I'd feel more comfortable myself if Sydney had blood tests done to make sure he's fine, even if you need to save up for it.
May I ask one thing though... can you get us a photo of his droppings? A regular one during the day and his first morning poop? I'm curious to know if they are normal.