In the last three years I've had only one problem of a partially blocked BD microfine+, but quite a number of problems with bent GlucoRX ones fresh out of the box. which lead to a serious debate with surgery who wanted me to continue with the Gluco ones because they were cheaper!! Had to point out to them that it was false economy given the number of Gluco ones I was having to throw away unused because of manufacturing faults.
I switched from BD autoshield to BD micro fine. Ultra really pleased with them. I follow bd's advice and don't bother squeezing flesh to inject and have never had pain from them