Sticking with the same bulb, it's 20 to 50% more expensive, much better light (in my experience) and another cost hit of perhaps 20% because they don't last as long as standard output bulbs.
Since we are all pretty much over-driving our lamps in North America as it is (due to output limitations in automotive regulations) I'd say Low plus High beams.
I always run them but you have to consider the added costs. Some people won't bite for that reason; personally I feel safety is a poor choice when slashing budgets.