Nice photos! They are all beautiful flowers but I still prefer the singles versus the doubles.
I've had aphids on my quinces (both flowering and Chinese) every spring. The first year they did a fair amount of damage to the new growth before I realized what was going on. Since then I've paid more attention and dislodged them manually (by hand or with water spray). I also move all the ladybugs I can find onto the quinces, as they will devour the aphids. We tend to have a lot of ladybugs around here for some reason, and often the young (larval stage) can be found on benches, potted plants, etc (they blow out of the trees). So I just move them where they are needed.
Chris