Hello there, i live in England as well and it does sound like the pain management is much better everywhere but in England.
I had the trial spinal cord stimulator implant fitted in oct 08 and am waiting for the re-fitting of it because they put the last electrode in the wrong place & i had some kind of allergic reaction to the external trial wire.
Here is the website that i've been on when i was researching the scs: www.medtronic.com
this is the company that actully make the scs device.
The batterys life span depends on which device they use for your implant, how often you use it, how high you have the settings, and how many electrodes you have working, but after doing lots of research the dr's think that the non-rechargeable device would need the battery replacing between every 3-5 years.
When you have the trial stimulator fitted it only takes about 1 hour, they give you a local to numb the area that they are working on and can usually go home the next day.
A few tips that i found out after getting home after having my trial fitted, get a bum bag (not very trendy, i know) but there is quite a lot of temporary wire/battery pack to carry around and if you where to drop it, it would hurt because the temporary wires are stiched to your muscles, so its handy to have a little bum bag under your cloths with your temporary trial wires & battery pack in, also get a rubber ring, because you wont be able to lean or lie down on your stiches in your back so i got a rubber ring to lean on so the stiches where in the hole of the ring so nothing was touching them, and it worked a treat.
The sensation that you get from the scs is amazing, i had it in for 2 weeks before they took it back out and its a fantastic feeling, if only the sensation that i had was in my back which is where i need it, and not in my leg and boob!
Have you ever tried using a TENS machine? its very simular to the sensation that a TENS machine gives you, only 1 million times as good & lots more effective, its a bit of pain having to carry around the trial wires/battery pack but its so worth it in the end, the trial only lasts for about 2 weeks. (depending on which hospital you have it done as)
If you type neurostimulation or spinal cord stimulation on the internet it comes up with quite a few sites with information on about the scs. I hope this information helps and hope it helps you make a decision