Review (1/5): Vacuum creates more problems than it solves.
So let me start off by telling you how I use this trimmer. I have very short hair, and about once a month, I will set the trimmer on the longest length setting and just trim my entire head: beard, moustache, hair, and even eyebrows.
I had never heard of a vacuum on a trimmer before this, and I thought, well that sounds allright, although I had already solved the problem of the mess by simply trimming outside with a handheld mirror.
The vacuum is very easily clogged when trimming, perhaps because I wait too long between uses, but that is how I use it. I don't want to trim up every single week. That's one of the reasons I have a beard in the first place. Once the vacuum clogs, you must stop the trimmer, remove the length adjuster thingy, and clear all the hair from the sliding vacuum trap door thingy. This happens so often that there is rarely any hair in the receptacle because it all gets trapped in the vacuum orifice.
Another problem, which is exacerbated by the need to frequently remove it, is the fact the the length adjuster does not fit easily and firmly in place. I often put it back on and start trimming, thinking it is in place, and it slides down, not from pressure, but because it wasn't locked into the grooves to begin with, even though it felt like it was. So just about every time I use it, I end up with a patch of extra short hair somewhere on my head.
One other thing I might mention, is that this trimmer will not trim while it is plugged in. You had better make sure you have enough juice in the battery to do the job before you start, or you will arrive either late or half-trimmed. I discovered this fact on Valentine's Day. Luckily my girl thought I looked cute with multiple length hairs sticking up in all directions.
These problems, combined with the fact that I really miss the smaller extendable moustache blade from my old trimmer (which was also nice for trimming around the ears), will lead me to not buy this, or any other vacuum-equipped trimmer in the future. In fact, I may end up just sending this one over to Goodwill in the near future.
All these issues may not be a problem if you like to trim more regularly. But this model is not for me.