"A share in any aircraft comes with it's problems, primarily that you are sharing it with other people which always leads to mostly small but sometimes large conflicts of interest."
I've been a member of the same group (6 - was once 8) for almost 22 years. You are the most important one to control whether the conflicts are small or become large. You could lose many of the benefits of being on a permit if problems have to be handled on your own - or possibly passed to a repair organisation. (e.g. in July, a cracked exhaust on a strip away from our home airfield and hangar.)