Charter Arms? Let's just say that when I bought a Charter Bulldog on impulse in the 1980's, then closely examined it later, I was a bit afraid to shoot such a poorly-fitted piece of machinery, and traded it away unfired. Whether today's Charter is any better, I cannot say.
I have not fired an LCR, but based on Ruger's excellent reputation for customer service, and the rugged durability of Ruger products I own now, I would go with the LCR, of the three weapons mentioned in the original post. I have never had to use Ruger's customer service, and some of my Ruger revolvers have been used HARD. My love for the SP101 and GP100 is well-documented on this and other forums.
I also have strong affection for the S&W Model 642. Mine is actually designated "M460" on the frame, from a run of 642-derived Performance Center revolvers built in the 1990's, when S&W gave many such runs of weapons their own model numbers, and yes, S&W did indeed re-use that model number in the 21st Century for an X-frame.
FWIW, I have an SP101, in a Kramer pocket holster, in my pocket right now. I mostly use pocket carry around the house now, but have pocket-carried a pair of SP101 snubbies in the front pockets of Wrangler Riata pleated Western-styled slacks in the past, when going to court, and one pocketed SP101 in the front pockets of other pants, in public. (Yes, I am legal to be armed in the local courthouses; court attendance is considered on-duty.)
I will probably by an LCR sooner or later. I can't see myself ever buying a Taurus or Charter Arms product.