Rail benders are section specific and ideally best obtained for the specific manufacturer.
Some are multi head but if you are only using one make then it doesnt matter,Personally any rail is best bent using a bender to avoid distortion.
Belly bending seems to work fine for brass and nickle silver code 250. You should be able to get an inexpensive bender for this rail though, I think Llagas Creek has one at a reasonable price.
I would opt for the bender, and get the rails perfect before putting in the tie strips. Often belly bending does not curve the rail ends well, so at the rail joints you have track that is too straight.
Regards, Greg
Visit my site: http://www.elmassian.com - lots of tips on locos, rolling stock and more.
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I belly bend my code 335 stainless, granted not for the mainline curves but wherever I need an odd curve for a spur or siding. It works just fine. As long as your not looking for a super smooth curves you will not need a rail bender.
-Brian
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