Some tests :

File 2'400'000'000 Bytes ~ 2.2 GiB and FAT28 volume

FreeDOS kernel is able to write and read > 2 GiB
now (> 4 GiB untested), this was not the case
in the past (definitely 2036, 2038, 2039 ???).

EDRDOS can write and read > 4 GiB too.

kernel   direc  time   performanc  slow
-------  -----  -----  ----------  ----
EDRDOS   read   150 s  15.3 MiB/s  2.2x
FreeDOS  read   168 s  13.6 MiB/s  2.4x
EDRDOS   write  384 s   6   MiB/s  5.5x
FreeDOS  write  512 s   4.5 MiB/s  7.4x
-------  -----  -----  ----------  ----
ME/98    write                                 usually pretty fast (FAT28)
XP/NT    write         ca 1 MiB/s  ca 33x !!!  slow as hell (NTSC)

Malicious data corruption BUG's (encrypted 7-ZIP,
FAT16 vs FAT28 uninitialized var) not really tested.

The "Can't-write-with-FSINFO-$FFFF'FFFF-BUG" (minor) seems fixed.

> Enhanced DR-DOS 7.01.08 WIP (23.7.2009) based on Caldera OpenDOS 7.01
> Copyright (c) 1976, 1997 Caldera, Inc. All rights reserved.
> Patches to original OpenDOS source code Copyright (c) 2002-2009 Udo Kuhnt

> FreeCom version 0.84-pre2 XMS_Swap [Aug 28 2006 00:29:00]
> DOS version 7.10
> FreeDOS kernel 2040 (build 2040 OEM:0xfd) [compiled Jun 21 2011]

Because of the very inferior performance of FreeDOS, I might
continue using EDRDOS most of the time (and UI21DEB to
workaround its BUG's) and have little chance to test the FreeDOS
kernel thoroughly ... so if there are still critical data
corruption BUG's, it may take a long time until I discover them.