I remember someone once calling the N95 the swiss army knife of mobile phones. This is a pretty accurate descripton of the N95. It has a hell of a lot of different features all packed into one device. So, why only 3 stars? Have you ever tried to use anything on a swiss army knife? It's a real pain compared to using the real thing. This is also true of the N95. Camera, GPS, media player, internet browser... All of these things are far inferior to using a dedicated device for varrious reasons. But what can you really expect from a device that 'does it all'?
First of, I know a lot of people have complained about the battery life on the N95. After following the instructions of another amazon reviewer (turn off 3g and auto wifi when you're not using them) it has never been an issue. If you really need the battery to last all week, buy a spare one. They cost about £10 and will fit in your wallet.
As a phone, this thing works pretty well. As you've come to expect from Nokia, everything loads quickly and the phone is very responsive. No problems there.
Getting UK maps onto your N95 requires you to download some software for your PC and then download the maps to your N95 from there. It's slightly more hassle than it should be but you should have any problems. A map of the UK takes up a bit over 100mb but you can choose to just download more specific regions if you don't travel much (England, Scotland, Wales and N Ireland). Unfortunately the GPS is absolutely terrible. I have the A-GPS firmware update and it's still very rare thar I every get a lock. I can leave it running for 10 minutes and still, nothing happens. I've been up and down the country with this phone and it makes absolutely no difference where I am, the GPS may as well not exist on the phone. However, having a full map of the UK is still handy, even without GPS, and using the internet to find nearby pubs, resturants and hotels is easy and acurrate.
The camera on the N95 is, in my opinion, extremely overated. Yes, it shoots at 5 megapixels, but this is utterly pointless considering the quality of the lense and the sensor. Yes, you can zoom right in to your blurry, out-of-focus photographs, but why bother? Most pictures taken with the N95 look good at about half full screen size. After that they begin looking more and more like an extremely compressed jpg. If you buy this phone, don't bother shooting at 5 megapixels, save yourself some memory and shoot at a lower resolution. The only reason I can see for the camera shooting at 5 mega pixels is for a selling point to impress the ignorant.
Having that little rant out the way, the camera, for a phone, is actually quite good. Movies look good so long as you shoot in good lighting and they run at a smooth frame rate. My only real annoyance about using the camera is the fact that it's so sluggish. It takes a good few seconds to start up, then a good few seconds to focus on your subject, then after taking the picture, you'll have to wait a while for the image to be processed. The whole thing takes too long (yes, I have the v12 firmware update, and no, it doesn't make much of a difference). The convienience of having a reasonable quality camera in your pocket at all times is almost enough to make up for these annoyances however, just don't expect to be able to whip it out and take a bunch of quick shots of a fast moving subject.
EDIT: My curiosity got the better of me and I eventually decided to do a little timed test. My N95 takes a full 14 seconds to launch the camera application, focus, take a picture and then process it. This is compared to a mere 2 seconds using my cannon IXUS (and this includes the time it takes the IXUS to turn on and extend the lens). The N95 takes a full 6 seconds to process an image, the IXUS takes half a second. I did these test several times, I got the same results.
The media player is probably my most used of any of the applications. With a decent sized micro sd card (I use a 4gb one, but you can now get 8gb) it's a good replacement for your MP3 player. Music is organised similarly to an iPod, you can view albums, artists, songs etc. I have only three minor grievances with the MP3 player. Firstly, getting music onto the sd card takes a LONG time. You'll want to transfer everything all at once and then leave your computer alone for an hour or so. Much slower than using an ipod. Secondly, there is an irratating hiss when the music is quiet, for example, song intros. This is usually drowned out once the song starts properly. Finally, the media controls are not instantly responsive. When pressing pause nothing happens for about 2 or 3 seconds and you might press the button again causing the song to stop, then start. I have learnt to trust the pause button, pressing it, closing the cover, putting it back in my pocket and knowing that the music will stop at any moment.
The N95 is advertised as being capable of displaying full webpages. While this is technically true, you can view the web in it's full, unhindered glory, you really shouldn't. The main problems is the browser simply cannot handle it without slowing down to a crawl. The N95's browser seems to be the weak link regarding the internet. Even on fast wifi, navigating real webpages is slow and frustrating. You're better off sticking to phone supported pages.
With all this said, I really like the N95. It's obviously not as good as using standalone devices for everything it does, but I think this is severly outweighed by having just one, small device in your pocket. The N95 is not perfect, but it does a good job of setting a new benchmark for all in one devices.