If you had fun the monhull, you will love the Wave. Super stable, very easy to handle, beginners to advanced sailors love this boat.
W/ 2 people it is quite fast. It will handle 4 easily, but speed is cut way down w/ added weight, but that is fine for a casual sail.
Setup and takedown are also easy.
I cannot comment directly about comarison to a Solsa, not even sure what it is. But I can safely say it is faster than just about any monohull out there
As for what to look for in a used one, do a search on this forum. There have been recent postings on that subject in the last couple of weeks in fact.
No worries about sailing terminology. If there is anything you are unsure about, feel free to ask. We all had to start somewhere