I would have to say pass it up...

The LA .15 and that small P-51 most likely won't give you a very good first impression of glow airplanes...

The LA .15 is a fairly reliable engine, but weak on power. I would look around for something else, maybe a .40 size trainer to start with. It's a BIG jump from the Slow-Stick to any glow powered airplane, which is why I recommend the trainer. Cruise around this forum for a while and you will find tons of information on trainers and engines.