makes me happy too.

White light is more aesthetically pleasing than sodium light, although I wouldn't apply that to uncoated mercury lamps, which are common in the USA but all but unseen in Britain, as I find those too cold. However, 35w ceramic metal halide produces almost the same amount of raw lumens as 80w mercury, albeit with a warmer and more pleasing colour temperature, and comsumes around half the power when you take into account gear losses.

Of course, ceramic metal halide is not quite as long life as mercury vapour, but that can be seen as an advantage. Mercury vapour lamps tend to just dim down to extinction, and some lighting authorities don't bother relamping their mercury lamps when they have dimmed down, because they haven't actually extinguished. Hence, you end up with a number of lamps producing perhaps half the light that they once did. Mercury allows for sloppy maintenance, which is something that is sadly on the increase in Britain it seems, even though mercury is dying out.

when they get old they turn green which is cool

they have the Fastest rate of Lumen Depreciation of all the HID lamps!

they have the Fastest rate of Lumen Depreciation of all the HID lamps!

Actually MH is faster!

the same rate over a shorter lifespan...

If you look, how LED lifetime is defined (they behave in very similar way as MV's - rarely fully dying, but mostly slowly dimming) and apply this methodology to MV's and CMH's, such MV lifetime is not much different from CMH calculated in the same way...
It is the burning time, when the total lumens of a large instalation drop to 70% of initial value. So it might be all lamps still burning, but emitting 70% of initial light (practically MV and LEDS), or 70% of lamps with 100% lumens burning (typical case is HPS).
CMH is somewhere between - there is some drop in lumens as well as some dying lamps.

But, joking aside, I actually prefer MBF (MV with phosphor) because they have a brilliant white light and if you look at it from a distance has a cool blue ring around the light.

Yes, exactly! For some reason I find the blue rays/rings around mercury lamps fascinating...

The light of Mercury lamps evokes peace in me, the light of HPS lamps irritates me.
They are the grandfathers of lighting, who began it all. They are above all other lamps and forever will be, with their unique and unforgettable atmosphere.

Pros: a good, classic. Nice, rich, soothing light. Can be clear so you can watch the arc tube without inflicting UV damaje on your eyes.

Have a liking to mercury lights,too-use the ones I salvaged from work-and some 100W mercury spotlights I bought from HD years ago off their sale table.Use both clear and coated lamps.But note-watching HID lights warm up at first is OK-but when the arc gets to intense-then its a bad thing for your eyes to keep watching unless you use a filter-the light gets to intense.Or you can look at the light from the fixture but not into the fixture during the last part of the warmup.Yes,thats a bad thing about mercury lights-they fade and fade-until they finally go out.MH tends to have violent EOL and HPS fades out and recycles-bad for the ignitor and ballast.At lest with those two its apparent thats its time to change the bulbs.