I repackage my solution. I ordered a bunch of drop bottles from US Plastics. I'd recommend the largest size dropper as they're not that large and a much more useful size for everything.
There's enough solution for 9+ days. I don't fill the reservoir full. Though if I go out for anything above 2 days, I also bring my glasses for night time and in case something of infection or whatever.
I use Accuvue 2's and just wear them until I lose, rip or it becomes very obvious that they should be replaced.
A very long time ago I saw something on TV claiming that basically all contact lenses were the same, whether daily, two week or whatever. I think it was 20/20 or some such show. Since then I've just worn them without worry and I've never (knock on wood) had an eye infection or ill effects.
Your mileage may vary, and depends on your comfort level (not the most credible source of info).
I often either forget my solution or the case (but never back-up lenses), and am too cheap to use my spares, so I just keep them in the whole time. I've gone 4 days without a problem.
I"ve also been told that your ethnicity dictates the amount of enzymes produced/need to clean lenses. Blond hair blue eyed the least, east Asians middle of the road, olive complected the most.
Again, none of this information is scientific or even researched, so take it as you may. I've just never had problems and have been wearing contacts for over 20 years.