What features are most important to you?
I know some of the heavier duty multitools are offering replaceable cutters, that's a good thing if you're using them a ton for that.
I honestly don't care much about the knife blade since I always carry a pocket folder, but I actually don't mind a serrated edge on a multitool.
Do you need locking pliers? Not many options, especially for under $100 (best IMHO is the Leatherman Crunch).
I like a good file, scissors, and a wood saw. My favorite "big" multitool that would fit you budget is the Leatherman Surge:
The T-shank tool that allows you to swamp various T-shank blades is brilliant. This is my serious "bushcraft" multitool kit. The Surge also has some of the best scissors I've seen on a multitool if that's an important tool for your.
Leatherman's 300 is a more traditional option and very heavy duty; right at the $100 mark as well.
While just over your budget, the Swiss Tool is a beast and extremely good QA/QC. I really like the tools on this one.
I have a SOG PowerAccess, and while I like the layout, I'm a little uncertain as to how robust it is. No issues, but it just seem to the same level of Leatherman and Victorinox.
Gerber is an option but I can't recall using one recently...for one-hand opening it's a nice option.
I have been using a Leatherman FREE recently and it's growing on me...not huge, but it's pretty decent and about the size of a Wave.
ROCK6