****Please note that I decided to tighten and revise this review, as I have had this razor for several years. I would now give it 4 stars for quality, 5 stars for value. My initial opinion was too negative.
This shaver provides a fairly standard Norelco (i.e. 3 head rotary shaver) shave. This is my third Norelco (well second, but I bought a third one recently), and by far the lowest priced one I've owned. If you like the Norelco shave, I think this is an excellent value. Of course, many prefer the Braun/Phillips type single head razors, but it seems there is no way to tell who will prefer which. If you have never tried a Norelco, this would be a good model to try because of the low price.
I now have an 8345 (which is the same as the 8340 but comes with extra heads) in addition to this one. The 8345 may be more money and newer, but they look, feel and shave fairly similarly. 8345 has more holes on the heads (can only be good I guess) but the motor sounds like it runs a lot slower. They seem to shave about as well, but the cheaper 7310 actually seems a bit gentler on the face (maybe because the 8345 has more holes but runs slower).
The 7310 feels generally solid enough and comfortable in the hand. Feels like all the Norelco's do, more or less. The pop up trimmer seems reasonably solid, and functions like all of these pop-up trimmers do. It will shave your sideburns, but you may or may not be satisfied with it. Nature of the beast.
The plug is also a little on the large side, which could be an issue for traveling, though not that bad really. I dont think it came with a travel case, but I could have misplaced it.
The battery cannot be changed easily because its welded in. At $40-50 for the razor, I suppose that is not a huge issue, but its not a plus factor either. I think this is true of all Norelcos.
This razor does hold a charge for quite a while, its good for several shaves without a recharge. However, there is no charge indicator at all. There is a green light that comes on when the razor is on, and another green light when its plugged in, but nothing changes as the battery gets low that I can see. You know it needs a charge when the motor starts to slow. A 5 or 10 minute emmergency charge is fine, so its not a great problem.
About the only difference between this razor and the $100+ Norelco I used to own was that the expensive one had a battery charge indicator. Maybe there was more metal and less plastic in the more expensive one, but...so what?
I have had this razor for 2 1/2 years, and use it about every other day. Maybe the battery doesnt last as long and the heads are duller, but its nothing I notice. I have put 0 money in it, and it still works well and compares well to my other electric razors.
Verdict: good shaver if you like Norelco's, and a bargain at $40-50. Spending more money is recommended if you want a batter charge indicator, but beyond that, not clear to me what you get for your extra money. If you like the Braun-type razors better, I dont know of any reason why this one would convert you, but I can otherwise recommend this razor pretty strongly.