I've bought the garklein for my teenage daughter. She’s an avid recorder collector and a quite decent player (garklein, sopranino, soprano, alto, tenor) when properly motivated.
The instrument is, as the name implies, small. Through a clever, slightly diagonal design of the tone holes it fits my daughters’ hands perfectly. Even I (a large adult male) can play it, but some practice would be needed to close holes reliably each and every time.
The tone of the instrument is loud, clear, and surprisingly stable. Intonation is accurate. The overtones that are generally characteristic for rosewood instruments aren’t all that obvious (could be out of hearing range?). So far, we haven’t been able to find the limit of the responsiveness of the instrument. The lowest tones are much easier to play than it’s usual for majority of baroque or baroque inspired instruments. It results in the limited range (an octave and a sixth) of the instrument. It can be debated whether this is a drawback or not. Ears of everyone in a hearing distance may indeed be quite thankful.
The instrument’s appearance is striking as one can expect of a rosewood one. The quality of the finish is very good and even the soft case doesn’t look cheap. It’s actually a very practical solution for such a compact instrument.