I prefer the original-type pad set with brown nylon tone boosters. MK VI pad sets had varying thicknesses - they weren't all the same. Like a few noted sax repair specialists, I like keeping a fine sax as close to original as possible, with the assumption that you like it as it is. The pads you can get now are different from the originals in one way, and the importance of this difference is debatable, but while they may look exactly like the originals, the tone booster is attached in the current fashion - the shaft on the back sticks through a hole in the pad and is melted down to secure it. The original method had a threaded shaft on the back of the booster that was affixed to the pad with a flat-headed brass screw. Technically, the current method is better because it reduces the weight of the key for faster action/less bounce.
Having found a tech who likes to do things like original, and having more than a full set of the boosters and screws from my saxes of the past, the next time I get pads the sax will be returned to original configuration. Actually when I got it in 1998 it still had more than half of its original pads so I'm not really expecting any big improvement. However, considering the MK VI is still regarded by many as the ultimate sax, its hard to argue with returning one to original set-up. Plus, with my sax, its not a big change, as I have always used only real cork and felt anyway although I have been using the modern replacement pads for a long time.
The very early MK VI did have metal boosters but that didn't last long as they replaced them with the nylon ones for several reasons, of which 'tone' probably was not one. The metal ones are heavier and tend to corrode. Personally, I think the current fads of gold and silver-plated boosters and boosters with special designs are silly. When you have a good, responsive sax, if you need more power you look at reeds/mouthpieces, not 'special' tone boosters. The whole idea of the tone booster is to replace the soft, sound-absorbing area of the pad inside the tone hole with a more reflective surface to reflect the sound back into the horn instead of being absorbed. Material and shape changes to the boosters have very little effect on the sound or playability.
BTW, the reason Selmer still uses thicker pads (.180, .185) is so the sax seals up better with minor irregularities like tone hole rims and/or the set-up. Thinner/harder pads only make leak elimination harder and contribute nothing to the sound or playability.
For me, this is a big deal because NOBODY puts a file to my tone holes. Nothing has changed on them since the sax was new. If they're not perfectly flat, live with it. Put the thick, soft pads on it like it originally had and the tone holes will be no problem. I do not like to lose a molecule of brass off my VI that I don't have to because it is irreplaceable.
So, there; how do you like those reasons for keeping the simple, plain brown tone boosters?
Oh, almost forgot - why did Selmer go with the metallic boosters for the 80 Super Action? They did it because the original Super Action, which was right before the MK VI, had metallic boosters, and metal boosters by this time had achieved legendary status because of being used on the early Selmers. In my view metal boosters are merely hype and never deserved such a fanatical following.
And just for you, Gordon, notice I have spaced my paragraphs!