I've never bothered with Sanditon because Austen didn't finish it and, really, no one could manage to complete it properly. I found this at the Simon's Town Library sale and couldn't resist, since it was cheap and right in front of me. Apparently this version is the one that was completed by a woman who sometimes calls herself Marie Dobbs and sometimes Ann Telscombe and quite possibly other things as well. Austen wrote the first eleven chapters before her illness caused her to be too weak to continue.
In the first eleven chapters we are introduced to Charlotte Heywood, likely to be the heroine, who is taken out of her home environment to Sanditon, a seaside resort, through a chance encounter with Mr and Mrs Parker. Mr Parker's relatives - an excessively meddlesome (Miss Diana Parker) and hypochondriac (Miss Parker and Mr Arthur Parker) family - come to visit and we meet his friends - the wealthy and autocratic Lady Denham, her repulsive relations Sir Edward and Miss Denham and her companion-niece Miss Brereton - in the neighbourhood.
The first eleven chapters are short, but there are all of Austen's hallmarks in the characters presented. The existence and likely arrival of other characters (the wealthy Miss Lambe from the West Indies, Mr Sidney Parker, the girls school) is mentioned and there things ended for many years.
This continuation is attempted to be in Austen's style and to have a plot similar to all her others (marriage after misunderstandings/difficulties for worthy couple). Unfortunately the other lady is not Austen and it shows. The plot is a simple romance with plenty of misdirection and meddling. There is none of Austen's brilliance and there is a shocking lack of character development. The heroine comes across as rather unintelligent and very priggish. Few of the characters are terribly likeable and most of the plotting is blazingly obvious.
It was a fun read, but unless you wish to read everything ever written that's remotely related to Austen, I wouldn't recommend it.