Are you sure that you use QUICK option in format? It's the only way you should format big/sfs partitions.
And don't use random block sizes, you get data loss after a while if you do so.
--clip--
The current partition size limits of SFS are:
64 GB with 512 bytes/block
128 GB with 1024 bytes/block
256 GB with 2048 bytes/block
512 GB with 4096 bytes/block
1 TB with 8192 bytes/block
2 TB with 16384 and 32768 bytes/block
--clap--
And why to make too big partitions... they are hard to back up or fix if something goes wrong

@stefcep
I guess nobody can fill it with Windows _software_ either

It's the general data files (music, videos) which fill up the space either on Amiga or on PC.