The studies I've seen on IVF babies seem to indicate they are 'generally' as healthy as naturally-conceived children. I have seen one big article published in the last few months that indicates a somewhat higher rate of birth defects (like a few percentage points). However, it is not yet known if that is linked to IVF treatments, or something to do with the patients' underlying infertility issues, or something else.
But that's on IVF in general. I don't recall any issues known with PGD specifically.
In our case, we also used MS, and the oldest MS children were only ~12 at the time, so I had to exercise a little judgement and faith on that decision.
So we have 2 IVF/MS/PGD children, they are just over two years old, and they are both healthy and normal to date. Their physical development has been very average, and cognitively, I'd say one is average and one is above average.
I do reserve a small risk of 'unknowns' possible in the future due to the technologies we used, but overall I feel secure and comfortable that our kids will be just fine. I wouldn't have proceeded otherwise.
BTW, when I was pregnant, my OB did tell me that ICSI babies had a higher chance of heart defects (like 3-4% higher), so I was tested for that, but in our case the girls were 100% healthy.