I have several Dandies (all three variants) AND an LT-25 that's been flying electrically for several years. I've also flown a DuskStick.

Several things:

Frist, the LT-25 is a VERY capable airplane. As long as it's flyable, you'll be flying it long after you pass the basic flight training curriculum with it. It is also about a sweet-natured a plane as you'd ever want to fly.

The DuskStick will be "easier" to fly that the LT-25, but since it's only three channels, it will be much more limited. Also, unless you up the power system a bit, it's not one you want to try on a day with much breeze. It IS very rugged and designed as a primary trainer.

The regular long-winged Dandy shares the same airfoil as the Duskstick (and, oddly enough, the LT-25 as well - they all use the real Clark-Y), but with the tapered tip panels it can tip stall. With the recommended washout you have to provoke it and it will then spin beautifully, but if you don't want a spin, well....... Also, the two-piece wing of the Dandy is joined by a thin ply joiner that will stand maybe one cartwheel before it breaks. I've replaced mine with an aluminum one. For this reason alone I'd choose the Duskstick over the "regular" Dandy, even though the latter is a much prettier airplane and has all the bits inside instead of hanging out on that carbon tube.

What you probably should REALLY be looking at if you're going to learn the basics on the LT-25 is the Dandy Sport. With the control throws set moderately it will fly actually quite a bit like a really light LT-25 (except that its ground handling is rather worse on smooth surfaces - the main gear is really too far forward). Turn up the throws and you'll be amazed at what it can do while still be relaxing to fly.

If you're getting antsy and can get the micro radio gear before you've soloed the LT, then it's definitely the Dusk Stick. If you wait until you HAVE soloed the LT, then I'd skip the three channel floater (unless that idea just really appeals to you - it does to me from time to time) and go right to the Dandy Sport.