Having gradually reduced my hair length down to a "Number 1" all over, I figured that I could carry on paying £3.00 to have it done by someone else, or I could just get myself suitably equipped, and do it myself.
I was a little pensive at what to get, having bought a Scherna male grooming trimmer a couple of years ago and found that to be shockingly poor, but then I saw the Philips QC5170 and decided it was worth a go.
I read the various user reviews, including the scatheing ones, but I have to say that I've had no problems with it what-so-ever. The manual clearly states that the number guide on that back is only a reference to tie-in to which of the two combs you have on at the time. They bear no relation to barber-shop "Grades" at all, so it's entirely your own fault if you go too low. I find a suitable length for me at the moment is with the smaller comb on and the setting at number 2. That to me roughly equals what I would have had as a "Number 1" at the barbers. I suspect going down to the 1 would be the rough equivalent to a Half-Grade at the barbers.
The rotating head is novel and not just a gimmick. It is genuinely useful for getting a better angle on doing your own hair. The comb attachments fit on in such a way as to give you a slightly cushioned feeling when you run the device over your head. The whole unit fits comfortably in the hand and isn't too heavy or ungainly.
The charge that the unit retains I find particularly good. One full charge seems to last for ages.
On the whole, I find the QC5170 to be an essential purchase for someone in the market for such a device, and I was pretty happy to pay £40.00 for it, so any less is practically a bargain!