One of the things I do which makes handling paper documents much easier, is to print out in booklet format. With a duplex A3 printer, I can print out a document of 60 A4 pages onto 15 sheets of A3 (in the US, I presume that you would make a booklet of Letter pages onto Tabloid sheets). Three staples, one near the top and bottom edge and one in the middle make a really secure binding.
Below around 60 pages this works really well, but above I start to get problems. Most long-arm staplers say they can cope with up to 25 sheets. Unfortunately, my experience is that at around 15 sheets, most long-arm staplers require you to make several attempts to staple (removing the mangled staple on each failed attempt) which makes the stapling process take much longer (even with a staple extractor).
When I get above 100 page documents, I have even more problems.
I have tried using a heavy duty stapler, which can staple up to 100 sheets (so 400 page documents, though above 50 sheets gets too unwieldy anyway) but you can only ever staple at the top and bottom edge, and even then you have to staple at an angle, since the width of the page doesn't fit into the throat of the stapler.
I've found a few long-arm staplers that are described as heavy duty but they look no different to normal long-arm staplers, so I doubt their claims to staple more than 25 sheets. What I'm really after is a long arm version of the Rexel Giant, with it's cantilever action to reduce the force required to staple many sheets, but I can't find one.