1) The quality of the screws provided could be better: the metal appears to be a little soft to me. The screw head does not appear to be a standard Posidriv or Phillips, so screwdrivers didn't fit well. Hence I found that it was quite easy to burr the crossheads when tightening them.
2) The instructions provided specify drilling a 3mm pilot hole for screws going into the wooden hand rail. This is too small and, after experimentation, I found 4mm is a better choice.
3) The decorative screws to secure the end-caps are particularly tricky to use because there is no way of gripping them beyond finger tight. I had to mess around opening out the pilot holes beyond 4mm to get to a size that worked for me. Maybe a design with a sunken Posidriv slot would be better.
Anyway, after overcoming these issues I was pleased with the result."