Nah - they went for cheap because these models aren't very popular. These same 3 systems didn't get any bids when they were listed a few weeks back - I posted about them
here hoping to get some interest generated. They started at $49.95 at that point, still not overly bad compared to what most sellers try to get out of them, and if the seller stuck to the $25 flat-rate shipping, you'd end up with the item for essentially the cost of shipping.
I honestly don't think that the rust was really a factor. The units I've seen, they were usually missing something on the bottom, and underneath was just a flat, metal plate. Mine has some slight surface rust on it. I haven't delved into the old product/service manuals to see exactly what was supposed to go there (if anything), as this plate was not part of the arm that could be pulled out to raise the angle on the system.
Also, hard drive or no, don't let that deter you. From my understanding, the hard drives in the Model 25 and 30 (not 30-286) were proprietary to those models and are pretty rare these days. Expect to pay big bucks for working drives, and slightly less big bucks for untested, likely-dead drives. To my mind, there's 2 8-bit slots in the Model 25; one for a Sound Blaster CT1350B and the other for an XT-IDE with an on-board CF. Problem solved!
Of course if you wanted to be more authentic, get an old 8-bit SCSI card and toss in a SCSI drive for those nice mechanical drive sounds
Also.. if you get one and need parts, PM me. I've two extra planars and daughtercards and stuff. Though I guess I should test them one of these days...