It's decent, but is not the XR-E/R2 type emitter pictured. It is in the same XR-E type package, but has a much smaller die with only two elements and two bond wires instead of the three elements and four bond wires pictured. It's not very bright. IIRC, only .6A at the tailcap too...
DX can be a crap shoot but I got good Cree green four bond wire type XR-Es and push them with 1400ma AMC7135 driver. Have an extra module for my SF Skyline 1 in green modded this way. My DX Cree red emitters look like factory rejects as the die is off center on all. YMMV
The best value is this 501 P60 light. It says Luxeon K2 but is a Cree. Driver is mild and I replaced with 1400ma AMC7135. No 8.4v sorry.
As green leds have typically the same forward voltage as white, and the XPE has a drive current of up to 1A, you may choose any of your favorite drivers.
One I like quite a bit is the DX version of the old Kennan driver. The last batch I ordered were configured to ouput 1.13 amps, just a slight overdrive. If you choose to change the output you can by changing the sense resistor. The formula can be found in the data sheet as I_led=.25V/R2 so in my case R2 was .220 ohms. If I wanted 1 amp output I would change it to .25 ohms. So I could replace the onboard 1206 resistor with one like this for 63 cents. But honestly I probably wouldn't bother.
Or you could consider this driver, I don't know what IC it uses but I don know that the specs that claim "output current 1A with P4 or 1.2A with Q5" are completely bogus, it's going to be one or the other regardless of bin.
*edit*
I just noticed your location. I imagine shipping to Croatia from Digikey is cost prohibitive, but I still recommend the same parts, you just need to find a supplier for your country.