Personally i dont't have those 2 specific models you mentioned. But i do own a Philips Avent handheld pump and a Medela PISA. After using Medela, i'm a huge fan. It's pure comfort. Using it is almost like getting a massage. But the Avent was excellent in removing hard lumps in especially in the beginning.
Brand-wise, i'll go with a Medela. You can try googling reviews. Good luck!