Hmmm, I've used a SD card since day 1 with firmware 1.0 and 1.4 with absolutely no problems so I'm not sure how "common" this problem is. Also, found fw 1.4 greatly improved battery life with a SD card. Since I've never really used the K without the card not sure if there is performance increase without it.
Are you still using 1.0? Are you planning to move to 1.4 or wait for 1.5?