for a beginner uke, the kala and lanikai series are great ukes for the money. i would stick with the mahogany or spruce series though. the advertised koa ukes do not use solid koa for the bodies. they are a koa laminate. but they come in body styles that are not offered in the lower model ukuleles.
what is your budget? by posting up that LU-21 standard, it doesnt look like much. but if you let us know what your spending limit is, we might be able to help you better.
personally, if you are going to get a beginner uke, you might want to cap off your spending limit at $200. if it seems high, think about the phrase "you get what you pay for". if it seems low, then hey, almost anything you get over that would be a pretty decent ukulele.
but shop around too. i found a place here in san diego that sells decent ukuleles for CHEAP. they are made by either sunlite or hilo (stick with the sunlites) and for a tenor or baritone, they go for about $50-60. these arent your novelty toy ukes either. i have a hilo baritone and my brother has a sunlite tenor. i instally pickups in both of them, set the action a little better and upgraded the strings and now they are actually pretty decent instruments. but for just about the same amount of money i put into each of those, you can get a lanikai LU-21T with pickup. my friend owns one and its a decent piece as well.
