Not all recorders work equally well, especially
with Commodore computers which use custom
recorders and a sort-of-digital semi-square wave
instead of 'normal' audio sine waves.
A better quality recorder does not necessarily
translate into a better chance of successful
recordings.
Amazingly for computer data I have had a lot of
success with the Radio Shack CCR82 (the little one)
Mine needed a new drive belt after about 20 years,
but that it all that went wrong with it, and I even used it
with a PET (with a custom interface).
It's horrible for audio recording, of course..
-tony