I'd recommend Penny's Esperanto course without hesitation to anyone who is in any way inclined to learning another language. The language itself is surprisingly almost intuitive once  the basic guidelines have been absorbed and are applied. As Penny pointed out - anyone could credibly become fluent in a fraction of the time required to learn any other national language. One advantage of learning Esperanto I was particularly impressed with was that it is a key to opening the doors to many different cultures as Esperantists (the speakers of Esperanto) all come from many different nations. Contrast this with learning a national language where cultural exposure becomes very much more limited to the cultures of the countries where that language is spoken.

Penny's warm, sensitive and enthusiastic approach to teaching Esperanto went a long way toward smoothing the learning process too. Admittedly our 'class' was small with the advantage that all the 'pupils' were well known to each other, however her confidence, manner and range of techniques for getting the subject across would, I am sure, work equally well in larger groups with more disparate backgrounds.