You may want to just keep the sliders and add screens if you want the cats to stay inside. I have Pella sliders with a screen that's on the interior side of the sliding door and I consider it perfect for use with pets. It can be latched/locked so there's no chance my cat can get outside. Since your cats are indoor/outdoor now, consider doing what holly mentioned. My cat has a cat door in the BR that opens to a wire tunnel. The tunnel then leads to a 10', six ft. high kennel that sits in the corner of the deck. Makes for a happy cat..........

I am Doug the Screen guy the owner of Screen Solutions Inc the maker of the Plisse screen. While we can never guarantee a pet will not find a way to get under our screens we have had good results lots of customers. Some customers have contacted us after the purchase having problems with their cats and we have been able to help them figure a way to make the Plisse secure. If judander contacts us we may be able to help. Here is a link that might be useful: Plissescreen

I am always a fan of less working parts. Given the availability of high visibility screening these days, seems like a less important option to me to be perfectly honest. That being said, we have installed the retractable screen equip windows in a couple of applications and have not yet had a service issue on them. They don't amount to much of our product, but those that we have installed have been fine. A quick tap of the screen would probably clear out any bugs that are still viable before you close up the screen and window.

I visited the showroom with the Kolbe windows today. They had a casement set up with both the hinged screen (left), and the pull down (right). Here they are both closed: Here is the retractable screen open. You can see the black brush border that is the bottom of the screen piece here: And a shot of it half pulled down (it won't stay in this position, it either lock in place at the very bottom or shoots back up like a roller shade) But you can at least see how much frame it has. I didn't get to ask about how easy it is to repair or replace, or what the upcharge is per window. (This is a lumberyard, and they're not terribly interested in people who wander in off the street - they pretty much sell to contractors. We'll be meeting with their window guy later and I'll ask then) (Edited to fix the photos)