Hi Terry,
I've been experimenting with convex and flat barrier and ring combinations lately, so here's my 2 cents. I don't notice any difference in how a convex barrier feels compared to a flat barrier, so I can't comment on that. In regards to barrier rings... their primary function is to fill in any uneven skin (divots, dips, creases) to provide the barrier adhesive a nice flat surface to stick to. So if you have only one or two spots where the skin is uneven, you can snip off pieces of the ring and apply those to only those areas of skin that need to be brought up to skin level. If your skin around your stoma is slightly uneven in a number of spots, then you can thin down the ring with a rolling pin, so it's not thicker than it needs to be. Just make sure to use some plastic sheet between the rolling pin and the ring (I use the plastic wrapper my barrier comes in) or the ring will stick like glue to the rolling pin. Going the other way, if your skin is really uneven, you can stack 2 rings together. So you have lots of options. I'd suggest you try a few different things and see what works because what works and what does not isn't always obvious. The first time I tried a flat barrier last week, I did so with a convex ring. It all went on great... and I was sure it was going to be a winning combo... but it leaked later that same day!
Regards,
Bob