I've been poking around the community for a couple days and have found a lot of helpful info, but not quite enough to make a final (initial?) decision.
Some background: I first got a Keeper (original/latex) several years ago (2005?). Nothing special went into the decision. I was under 30, no kids, and it was that or DivaCup at Whole Foods. Either way, I loved it. The length (never trimmed) and fit were good, capacity was just fine (there may have been a few times I had to empty it after 4-6 hrs, but usually 8-12 hrs was fine). After DS1 was born (2010, C-Section), I tried using it again but it was painful (post-partum dryness maybe? but it would mostly "catch" on my perineum). I think I may have had some minor and/or inconsistent leakage issues, but I attributed it to position problems associated with painful insertion (hard to say from memory, though). After a few months, I left it in too long and it developed an odor I couldn't get rid of, so I tossed it and used tampons until I got pregnant with DS2. Now after a 19 month hiatus, AF has returned after the (vbac) birth of DS2 (and after my 30th birthday), so I'm trying to pick a replacement. Money is tight enough that I don't want to do a lot of experimenting, but given the trouble I had after DS1, I think I might be better off trying something new.
I'm a runner now (in addition to chasing after my kids!), but I was relatively sedentary before. A couple threads seemed to indicate that stiffer is better for an active lifestyle. Is that right? I know the Keeper is the stiffest, so at what level does that become an issue (i.e. with the scale listed here, would anything down to 7.5 be stiff enough, or would I notice a difference even between a 10 and a 9?).
In terms of size, since I seemed to be tighter after my CS, and still seem relatively tight, should I try to stick close to the 41 mm of the smaller Keeper or was the pain I experienced after DS1 more likely an issue of something other than size? If I switch brands, how close should I be (i.e. would I notice a 1 mm difference either way? 2 mm?). Have any of you who used cups before and after kids/30 and found going up a size was no problem even if you didn't think you "needed" to? How does squishiness affect how comfortable a particular size feels/seals?
Thanks in advance for the input!