I've got a convex Longacre mirror in my car, and I'm not hugely thrilled with it. In our Lemons Miata, we're using just a clip-on mirror cover that's curved laterally, not convex. it doesn't change the focusing and depth perception near as much as what my Longacre does. It's also closer to my head and I have a pretty wide field of vision in it because of it. I prefer that mirror over the Longacre one in my car (which was 4x the price!)

In either car/mirror though, I can see everything from my helmet to about halfway out the right door. Thus I have no need for a right side mirror. On the left side, I use a small "F1 type" curved mirror: https://www.pegasusautoracing.com/pr...p?Product=5121


Keep in mind that you don't really need to be able to focus on a car coming up behind you. I glance at the mirrors and see if there's a fuzzy dot in it. If so, I have tons of room. If there's a bigger blob, I pay more attention. If I'm on a straight and can see the blob getting bigger, then I know I'd better be ready for a pass by a faster car.

That said, your run group includes GT1-3, so you have some fast cars running with you. it's a bit different than running STU where you're more equally matched in power and there's not at much closing speed. I have a lot more time to react to oncoming traffic at the end of a straight when they're passing me at 5-10mph differential vs. 50+mph!!

Will you be at TWS this weekend? would be happy to let you take a look at the mirrors I have set up in my car.. I think I have extra mounting brackets and possibly a leftover longacre that I cracked a corner on first installation. Let me know by tonight and I'll toss them in the trailer.