Well Steve...considering Mitchell 300's were consistantly sold over 50+ years...AND that sales of them on Ebay remain brisk...I would say that your opinion is not shared by MANY hundreds....if not thousands...of fisherman.
JMHO....and you ARE entitled to your opinion.
Brian...there's well over 200 current auctions of them on Ebay at the moment. I don't know if you are on there...but ya gotta beware IF you are...that just because someone on there SAYS the reel is in good shape mechanically...doesn't mean that it is. I could write a book on experiences while buying on there

I MAY have an extra one in good shape (the 6 models I referred to earlier were of Mitchell's in general)....so I'll take a look in the next couple of days. IF I have one...I'll PM you so that I can send pics to ya.
If for some reason I don't have a decent 300...there is a Life Member on here that has worked on reels for most of his life...and usually has a couple of 300's in his inventory. I trust him like a long-known brother / friend...and he has NEVER done me wrong on equipment.

he comes to the La Crosse Meet every year.

I DO know that I have spools that are in great shape....both large and small capacity.