I've used an electric razor ever since I first started shaving. They're quick, they're easy, and they're safe, especially compared to the standard blade. But where I did use a rechargeable before, I've since gone to just using a plug-in. The problem I had with rechargeables was, whether I left them plugged in all the time or ran them down and "deep cycled" them, it seemed like the batteries would consistently stop holding a charge before the blades would get dull.
The interesting thing about replacing blades, though, is that I never actually do it. I've found that the price for new blades is so expensive, and the price for a simple, plug-in electric razor is so cheap (because only the cheapest models are plug-in; the first feature that gets added as the price goes up is cordlessness), that it's just as cheap and twice as easy to buy a whole new razor than it is to find a set of blades that's compatible with the razor I already own.
Case in point: my last Norelco razor stopped cutting as well as it should. I went down to Wal-Mart to look at razors. Razor blade heads were $29 (and since I didn't know the model number of my razor off the top of my head, I wouldn't know which one to get, if a compatible set was there at all), and a new Panasonic razor was $31. Which leads to the inescapable conclusion that the razor itself — the housing, the motor, and even the flip-up trimmer and the blades contained therein — are worth a grand total of two dollars.
Which sounds about right, considering the flip-up trimmer on my old Norelco had also broken, being driven by a cheap piece of plastic. Buying new heads wouldn't fix that.