I'm sitting here looking at five meers in the ashtray near my desk, there are four more on the rack in my bedroom. At home I smoke them almost exclusively. Four of my meerschaums are at least 50 years old, very nicely colored. There is an almost even mix of screw-in bits to twist-ins. Only one pipe has a repair band on it and it is a twist-in bit.
Treat them with respect and they will last you a life-time. My meers do not go to the woodlot or on photo shoots. They do very well outside, on the deck or when watering the gardens. They do not go outside when the temperature goes south of 20f or so.
If properly constructed they should smoke well, same as any other pipe. The ornateness of the carving generally dictates the cost along with the rating of the block. Some block is better than other, there are some 60 grades of meerschaum. You can smoke a meer more consistently than a briar as the meer does not need the rest after a full day of use. That said, I do let them dry out a bit between bowls. They do not seem to need the day or two of rest like a briar does after a full day of smoking.
Other than those caveats, mine are treated fairly cavalierly. I hold the bowl when tapping out on the cork or in my palm. They get a pipe cleaner after a smoke and are more thoroughly cleaned once a month with my other pipes. I wash my hands carefully before lighting up. The bowl rests in my hand when I smoke one of my heavier, more ornate pipes, no cotton glove or handkerchief. The others I usually handle by the stem when the bowl is working.
I've not found, through experience, that any of the so-called stain enhancing waxes help in the staining process. Perhaps some of the other meerschaum aficionados have anecdotal evidence to the contrary. If so, please share.
I did have a friend, a photographer, who used cotton gloves when smoking a meerschaum. I am sure that was purely affectation. Everything he did with that pipe was done with a flourish. He dearly loved that pipe and loved showing it off and the whole pipe experience, loading and tamping just so. I wish I knew what his kids did with it. It really was nicely carved and had colored to a nice, deep chocolate color.
That said, if coloring a pipe is the reason you smoke the meer, I'd suggest a clean handkerchief between fingers and bowl when loading and cleaning, only so that you can't blame dirty hands or wax disturbance should the pipe not color as you expected. After the tobacco is lighted you should try and handle only the bit. Some meers color splotchy, some will go to a deep almost black color, others will stop coloring somewhere in between. I suspect coloring evenness and hue are almost entirely due to the porosity of the mineral and the wax application, quality of and depth of.
I smoke the meers more for cool smoking qualities, not for the coloring. Ergo, I'm not as careful a smoker as one who is more concerned with coloring than smoking attributes. While I do enjoy a nicely stained meer, it is not the driving reason I smoke one.