if you want to trim thick tradeshow pannels, i suggest you dont get a rotary cutter, get a keencut javelin ( mounts onto work bench ), or the sabre. or get a wall mounted trimmer like a seal multi-cut or fletcher. But if you insist on getting a rotary trimmer, the best are Neolt brand. I have 2 and use them everyday.
I agree that a rotary cutter is the way to go. It will cut long panels in one pass without issues. Just be sure to get a size that is appropriate for the largest typical graphic you cut.
What model of Neolt do you have? I ran an electric one for a while and it was a piece of crap. I ended up having to add a bunch of shims to get it to hold media and it got to the point where I partially disassembled it and ran it by hand. Maybe the manual ones are better?