12V/1 LED driver recommendations

I'm looking for suggestions for a 1 LED driver running off a 12V supply.
I'd prefer a single drive current, either fixed in the 700mA-1A range, or something I could set myself, and max dimensions of an inch or so.

Has anyone had good or bad experience with drivers from the cheaper suppliers?
I'm likely building something for someone else, so they'd be paying, and I'd be tempted to err on the side of quality as long as it isn't horribly expensive, but wouldn't want to buy something too fancy, of which I was only going to use a fraction of the capabilities.

I thought DX had a driver that went to 18 Volts, I just tried to find it but can't. I did find a LED drop in. http://www.dealextreme.com/details.dx/sku.6090
Norm

Check out these drivers:

http://www.luxeonstar.com/category.php?id=241&link_str=240::241

I am currently using this model: http://www.luxeonstar.com/item.php?id=5188&link_str=240::241::1396&partno=3023-D-E-700



which is basically a 700 ma constant current source that can take inputs up to 32V. I am driving two Luxeon V LED's in series off an 18 volt battery. It only needs a 1 volt differential over the total forward voltage of the LEDs. Works great.

Thanks for the suggestions.
I'll have to do some measurement when I get my hands on the torch body to see just how much room I have. The buckpuck does have the advantage of being able to trim the current, which could be useful.
I guess the 1000mA buckpuck throttled back to 70% output behaves essentially like the 700mA one (ie the only difference is some component setting the maximum output)?

There does seem to be an 18v buck converter on Kaidomain, but maybe there was also something similar on DX.