Hi, sunsurfer. Here is an old thread on SD cards. I typically buy Sandisk. They cost a bit more but have good performance.
https://www.mobileread.com/forums/sho...d.php?t=106978
Right now I have 209 notes, and I'm not noticing any slowness in opening books. I have had that issue in the past. I have found that I have certain books that I know will cause a slowdown. They are typically big books with complex formatting and lots of highlights + typewritten notes. When that happens, I power down and then back up, and the speed returns to normal. My typical process is that I use the Reader Library software to sync/merge all of my notes between the copies of ebooks on my computer and on my reader. When I am done with a book, I will typically save the notes to an RTF file with the Sony software and then delete them. That way I keep a revolving amount of notes somewhere between 100 - 300.
If the notes are that important, then I keep backup files. I have successfully restored notes from my backups. It's another option besides exporting the RTF file. Here is an old thread on notes that might give you some ideas. Warning: it's a bit complicated though and not without effort.
https://www.mobileread.com/forums/sho...d.php?t=120302
Hope that helps!
