For another take from an experienced user group:
http://soldiersystems.net/2011/07/22/sasr-wo-criticizes-the-austeyr-f88/
Note VERY CAREFULLY that troops under fire in combat went to the M4 specifically because of design deficiencies in the issue bullpup.
Not only the mag change, the length of pull issue with armor is mentioned, along with others. Again, it's not me, it's their own professional user base. It's not just one persons opinion, it's a command level dump of the weapon in a combat zone for something that they say works better. Senior decision makers had to mull over real combat use and spend money to back up their choice.
The one Army in the world that could prove the bullpup's combat usefulness is very clearly saying that when their life is on the line, they don't want it. They aren't sucked in by all the hype, and they would know. When you're under fire, an unwieldy gun with obtuse mag changes suddenly becomes much more critical than a sunny Saturday afternoon at the range.
How they got there is important - they cut down M16's and saw they were better, they were just too old to rely on. So, they bought new M4's and moved out.
The experts in bullpup use are saying, when your life is on the line, buddy, dump it and get an M4.
If that sticks in some craws, well, they can't accept professionally qualified and experienced combat veterans' opinion on what they prefer to use in war - soldiers who got to try them back to back.
Bullpups are a curio and relic, a sideshow in the progress of firearms.