After reading several posts about experimenting with strings, I decided to try it. I've been buying Mahalos on Amazon and have given away 2 so far in my goal to be the Johnny Appleseed of ukes. I put Aquilas on them which really helps the sound.
I also have a new banjo uke--an aNueNue. It's got a nice antiqued look and pretty good sound. The uke came with Orca strings, which are black flourocarbon and nice and bright in tone. I put a set of Orcas on my Bushman Jenny concert (replacing Aquilas) and think they help liven that uke, too.
My Pono tenor came with some unknown black strings that are very thin, which gave it a nice, but not very rich tone. Since Pono is made by Ko'olau, I thought their strings might work, so I put on a set of low G (wound 4th) Ko'olau Golds on it and really like the difference. The tone is much warmer and it is much easier to put out the volume. The low G is nice on the tenor, too.