I'm a big fan of the good ol' Northwest Short Line "Chopper" and "True Sander" ( http://www.nwsl.com/uploads/chap1_TOOLS_09-15.pdf ).
i can't say I've noticed the wobble problem Don mentioned, perhaps because I scarcely ever chop anything more than 1/32" thick. But the potential for wobble is there, all right.
A few years ago I got an e-mail from Northwest Short Line (I guess they'd gotten my address because I'd bought something from Walthers), telling me that MicroMark had stolen the NWSL designs and was marketing cheaper copies. NWSL asked modelers to refrain from buying the MicroMark products.
I'm going to comply with that request - though I'll still buy other stuff from MicroMark. The company sells so many other good tools and other products that I figure a full-scale boycott would hurt me worse.
The Chopper does a nice job with small miters. I do suggest replacing the little plastic angle guides with a small pair of draftsman's triangles, though. The latter are longer and beefier, and more likely to get you consistent angles. You can pick up a pair of small ones for less than $10.00 - and they'll come in handy for all sorts of other jobs.
I'm also a big fan of Zona saws, which are the best of that sort of saw I've found. They're also among the biggest bargains in modeling: http://www.micromark.com/4-in-1-zona-saw-set,8293.html .
For bigger jobs, I like the set of small Japanese saws I bought from Lee Valley: http://www.leevalley.com/US/Wood/page.aspx?p=58686&cat=1,42884 .
Japanese saws take a little practice, but once you're used to them they work beautifully. The big differences from western saws are that the Japanese ones cut on the pull stroke, and the teeth are filed in a different, more sophisticated pattern. Since the Japanese saw blade is under tension when it's cutting, it can be thinner, and require less force. Try one; you'll like it.
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