I've tried a few brands of ink and all have delivered in terms of colour. How they live within my pen's feed and filler mechanism is another matter however, since a number have contained elements that gum up the works if not drained and cleaned after every use!
The best fire and forget inks I've used so far are the Pelikan brands, with both 4001 and the Edelstein lines being truly excellent. Key things I like about these inks are:
They don't readily bleed
They don't penetrate thinner paper as much as others I've tried
They stay fluid and flow easily within the pen for a long time
They wash out of the pen without too much effort
They don't corrode my nibs or gold plating
They provide a good range of colours, although since they dropped the truly excellent Edelstein Amber, there's not much available at the yellow end of the spectrum - (blatant hint by the way Pelikan!)
They are very affordable (especially the 4001 series).
There would have to be something truly exceptional about a product before I'd be lured to another ink brand now, since I tend to be conservative and stick with the products I trust.
That's how I feel about MB Inks...I owned Pelikan Edelstein Sapphire...Great ink for my uses.