I used fem seeds for my last grow and I just planted another pack today. My only real complaint with my first experience with fem seeds is that not all the plants grew as uniformly as I would have liked. Out of 9 seeds(of 10, one never cracked): One was a flat-out runt that didn't survive transplant. 2 were strong, but about 1-2 feet shorter than the rest, which were about 4 feet. 3 were much taller than the rest, and the other 3 were about a foot shorter than the tallest.
Again, I would like for all the girls to grow at the same rate, or as much as reasonably possible. I know uneven growth can occur with non-fem seeds, but I happen to think that the fems are a little less likely to grow uniformly. This is just one grower's opinion, though. Bottom line, I honestly would not hesitate to recommend feminized seeds, but it's clear to me why so many people only grow from clones. Another thing to consider is the quality of the seeds and the vendor you obtained them from. You really have no clue what you're getting if you don't buy from a reputable seller.