Bit recommendations?

Hi,
I need some advice:
Material: 18mm Birch plywood

I have experimented with both 1/8" and 1/4" bits as follows:
Straight cut: cut fills with compacted debris, causing the bit to work loose (both 1/8" and 1/4" bits do this)
Upcut: fine - no issues with debris - only tried 1/8" bits so far
Compression: not tried yet.

Question: Would you recommend 1/8" or 1/4" bits for about a 10-hour job cutting out 60+ parts from a full sheet of 18mm plywood? Are 1/8" bits up to the task, or should I opt for 1/4" bits?

I’m using a Makita. I have read wildly differing opinions on various forums regarding feeds and speeds ranging from using the lowest router speed possible, right up to max RPM. One piece of advice (from this forum) was to use 30k RPM, 2-flute upcut bit, 20mm/sec feed and 4mm DOC. I’ve tried this, and it seems to work fine. But it isn’t even close to Ryan’s recommendations.

Question: If you were going to do a long cut using 18mm ply, what bit/speed/feed would you suggest? I know all machines are different, but perhaps you’ve had some experience cutting 18mm material?

Duncan