The only real way to improve HD raw speeds are to install a hardware board like FastATA MK III or Blizzard SCSI... 
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While the FastATA MKIII will do raw disk speeds from about 3.8Mb/s on an 030 and 5.6Mb/s on an 060 equipped Amiga...
I can confirm a performance increase with FastATA on an A3000.
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In general, I have not yet tried PFS. I am intrigued though because I have mostly heard very good things about it. It is on my list of things to try. It seems like the most I hear about it involve improved reliability and safety over the others. I have had good experience with SFS but will give PFS a go. Piru (MorphOS) thinks very highly of this PFS, and wasted no time in the initial porting of it for MorphOS.
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The new IceFS is coming into stream as well. I think a 68K port is planned for. It would be interesting to hear more of this one. Its developer is quite busy on it and has continually been updating it.
