Personally I don't *mind* hicaps (I have three for my MP5s, but also have midcaps and locaps which I use all the time) but I have a hard time trusting them. First time I went to Op:Quick Pass (2005) I only had 4 TM locaps (200rds total) and one hicap (200rds) to do the day with, and considering the large size of the field (must be roughly 800m between bases at the most), reloading was always a long drawn out affair (add in the extremem wind and ranges, being effective on semi is pretty useless). I found my hicap jammed on me halfway through, and only had locaps to rely on. A few days later I took my hicap apart, found a single grain of sand stuck between the gear teeth had caused the problem. It worked perfectly after that, but since then I've avoided as much as possible using my highcaps (although I will loan them to players that are MP5 mag limited, one bud of mine only has two midcaps).
I fit very well into milsim scenarios, enjoy them a lot, but I'm not anal about realistic ammo loadouts like some. I've always shot 28rd mags the same as I do hicaps.