KRA - truth be known, if I was to go back for one - it would be the first one. The whole table is there, the spool stand everything. I just don't know that I have the space, though DH said it would probably be best if I got it rather than someone who knows less about them because I'm less likely to kill myself trying to get it running.
I feel bad for it too. The part sitting in front if it belongs to it but could easily be lost. The pedal chains are joined and shouldn't be... I'm sure some newbs would have nightmares about threading the Frankenstein bolts..
I'd finally get my dedicated Chainstitch machine too this way...
The third one - the manual shows the balance wheel at the back as having stitch length built into it. There's a notch in the hub that shows the number the stitch length is set to. I saw no mention in the manual about the handwheel half way down the arm. DH thought maybe it was the same as the back but within a reasonable distance, but then why have the one at the back?
I didn't get far enough to the back to see if there was a belt groove on the third one but I bet it's a chore to treadle! It's belt driven inside though.
The first one has a motor below the table but I have no idea what sort of table the 3rd one was on. The manual for the 113W110 says that it was for "2 line lock-stitching in balloons, aircraft work, for sewing celluloid into automobile curtains and for stitching articles of large and awkward sizes. It has an extra long arm and is equipped with a puller feed in addition to a drop feed and will sew up to 6 thicknesses of No. 8 Duck."