I went for both too. Far east no name ebay jobs work well enough. The corded ones don't seem to last that long though, so I'd even suggest getting more than one of those to have a spare. The wireless one I got works just like a corded one without a cord, so you can hold it down for continuous shooting.
As for long exposure, how long is long? With wireless you do have the additional complication of battery life to consider.
Also if it is of any interest or use, there are timer settable ones for a bit more cost.
_________________Canon DSLRs: 7D, 5D2, 1D, 600D, 450D full spectrum, 300D IR mod
Lenses: EF 35/2, 50/1.8, 85/1.8, 135/2+SF, 28-80 V, 70-300L, 100-400L, TS-E 24/3.5L, MP-E 65, EF-S 15-85 IS
3rd party: Zeiss 2/50 makro, Samyang 8mm fisheye, Sigma 150 macro, 120-300 f/2.8 OS, Celestron 1325/13
Tinies: Sony HX9V.