My experience is that MB use Bosch (Platinum) on the more mundane cars and NGK (Iridium) on the high performance once.
My car came factory fitted with Bosch though when I replaced them I opted for MB NGK ones, which were the right model for my car according to the NGK catalogue - and they were available from MB though not listed on MB EPC for my particular car, if this makes sense.
NGK Iridium are probably the better plugs, compared to Bosch - though you are not likely to actually notice the difference... and while the Iridium plugs may last longer, as you said this does not really matter to you.
And the dual or quad electrode spark plugs do not have a better spark... their advantage is that they last longer and do not need gap adjusting, but they have no advantage from the performance point of view. If they are listed for you car by the manufacturer, then fine - my 1979 Alfetta had quad-electrode plugs as standard (made by Lodge), as did my 2001 Vauxhall (made by Bosch). But I wouldn't worry about 'upgrading' to dual or quad electrode plugs if they were not original fitment.
In short, for the same money I would go for NGK iridium, but the Bosch will be fine as well.
