We also use clear tape, and no film edge marking. As John said in his post, you can see where the splices are by lighting up the film roll. The lab splics mess with this now and then, but that's not a big deal.
My daughter sometimes puts a bit of post-it-note where the splice should be, so she can slow down the platter in time. It's not something that works for me, but it seems to for her.