I'll add a vote for the BMT tool, pricey as it is.
In my mind, the key to using moon clips is to have a pile of them so I can load/unload them while sitting in my easy chair watching the TV. At the range I don't spend a lot of time unloading and reloading...using my revolver is just like swapping magazines with a semi-auto. Also saves me from having to bend over to pick up my brass...unless I drop the whole clip, which I've been known to do.
Also, if you use quality clips they are not consumable items. They will have an impressively long service life. I use TK Custom stainless steel clips, but like the BMt Mooner, they're expensive, too. Sometimes, however, you do get what you pay for.