That's like asking to choose between The Pope and Martin Luther. Both have their good and bad points. They should both stand up well to a 235 or 261 as long as they are in good shape, and both are pretty easy to get ahold of. It all depends on what gear ratios you want. I have a 3- groove Saginaw 4 speed ready to go into my truck, mainly because I stunbled across it and bought it for $50 rebuilt, but also because it has the exact wide range gear ratios I want to match up to the 3.07 axle also ready to install. Some people argue that Muncies are stronger, but that isn't necessarily true.
