I've seen this type of problem on the FWD posting, and on the SAAB post. The first gear synchro will wear rapidly if used too early on stopping. I've seen people put the car in first at 15-20 mph while coasting to a stop, presumable since that is what an automatic would do. The synchro is forced to accelerate the input shaft to match the considerable first gear speed, and wears quickly if this is done all the time. I prefer to stop completely prior to shifting into first, but it is more a habit since I have 2 cars not synchronized into first at all.

'98 V70 5-spd '92 SAAB 5-spd '88 240 5-spd '71 Mercedes 4-spd '69 164 auto
'42 Packard 3-spd+OD 21 Packard 3-spd