So many mods, so little time.
If what you need is dependable, no-fuss performance in the 5-50' range, the SL-35X LA in either the SL-20X or MagCharger (or Mag 3D with bi pin mod) is hard to beat. You get a bright, meaty beam that is softly diffused due to the satiny finish of the reflector.
If you need 2 hours of runtime, then the stock MC bulb provides a focusable, white and tight beam good for 100'+ spotting when tightly focused but is less smooth up close and if defocused to be wider.
If you need the SL-type beam but longer runtime than the SL-35X LA, use the SL-20X LA (20W) for a softer, no-focus, yellower beam than the stock MC bulb.
If you need the maximum brightness of the SL-35X LA coupled with the focusability of the MagCharger system and a whiter beam, use the WA01160 bulb.
You really have so many options and they are all good ones. Some better than others but then that depends on your specific use requirements.
Wilkey