I feel qualified to write this because I have researched all about this product, as I was intending buying one. As it happens I went for another option. There was nothing particularly bad about the Sony NV-U52, just that going for another company was my personal preference.
This is a sat-nav, a navigation aid, and is small enough to fit into a pocket, handbag, or a glovebox, however I would recommend you to never leave it there due to the risk of theft. The weight is just under 300 grammes, and at just over four inches wide, it is, in my opinion, the the perfect size. The width of the actual screen is three & a half inches, and although this is measured diagonally, it is adequate.
The screen is a thin film transistor (TFT) and is of the "touch screen" variety. I find that touch screens are difficult to keep clean, but of course you should be using a pointer, not your grubby fingers. The battery is one of the modern LION ones (Lithium Iron), and this is charged by a USB plug, meaning you can charge it on the move in your vehicle, or at home using a laptop. The battery life is supposed to me up to 3 1/2 half hours, but we all know that is in perfect conditions with a brand new battery, fully charged. I would not realistically expect more than two hours, however, I personally would not recommend using any sat-nav without the charger.
Many devices these days have a bluetooth function, so you can make and receive calls using the device as a hands free kit. This one does not have this ability, but I do not regard this as a bad thing, I only make the point as a comparison. I do think the Sony NV-U52 looks good, but then is a functional item, although I would not buy any item purely on looks alone.
The built-in memory is 512mb, but it will accept a memory stick. The device will also download updates via the USB lead from your PC. The one I was looking at buying had full UK & Ireland coverage, but a European version is available on DVD as an optional extra. The only thing to remember with any sat-nav, is that tall buildings can shield the signal, and this model is no exception.
The mounting cradle is very good, easy to set up, and will stay attached to the windscreen. The Sony NV-U52 is simple to use, and you can enter either the address, POI (points of interest) or postcode (ZIP code). The voice instructions are clear and easy to follow, and I find the operation is very simple. Upon purchase you will find in the box:- the device itself, a USB charging lead, installation instructions, a carrying pouch, and a CD which is basically a manual. There is also the obligatory one year warranty. At the time of writing, there does not seem to be any out of date data, but of course roads are being changed all the time.
The cost was what I would call reasonable, but then it is a while since I priced it up. As with all electronics, I would advise against buying second-hand, and to shop around for discounts, especially at this time of year. This Sony device is sold with a free year's speed camera subscription at outlets here, quite a nice bonus. I am not particularly expert at electronics, but I do have a lot of experience of sat-nav devices, and this seemed to be very user-friendly.