The only difference between SH 205, Megafile 2o on the one side, and Megafile 30/60 on the other side is just one chip which does the drive data encoding, on the SH205/MF20 it is a MFM chip, in MF 30/60 it is the RLL chip. Also firmware is different, related to the different number of sectors on MFM versus RLL. The rest is identical.
Adding a 2nd drive is quite simple, i did it several times. Also the SH 204 controller can handle a second harddisk, but in the shoe box is no space for that.
Power without the Price. It's not a bug. It's a feature. _/|\_ATARI
1040STFM in PC-Tower (PAK68/2, OvrScn, 4 MB, 1GB SCSI, CD-ROM...) * 2x Falcon 030 32GB/14MB+ScrnBlstrIII * 2x TT030 73GB/20MB+Nova * 520/1040STFM * 520/1040STE * 260/520ST/+ * some Mega ST * 2x Mega STE 500MB/4MB+M.CoCo * Stacy * STBook * SLM605 * SLM804 * SLM605 * SMM804 * SH 204/205 * Megafile 30/44/60 * SF314 * SF354 * 5x Pofo * PC3