If you really only wanted to spend 100 Bucks I would buy the Marmot PreCip ( 14 ounces as advertised on REI). I have owned one since 1996 when i did my first long trip to Bosnia, I have since carried the same jacket and pants around half of Europe and the Middle East, not to mention its my go to jacket for backpacking and back country trips ( fishing and hunting). Some of you are saying, Middle East ! Rain ? oh yeah man, it can come down and it can rain for days. I believe it made Backpacker Magazines Editors choice award. There are plenty of reviews on the internet, some good and some bad. Additionally you can purchase matching pants (12 ounces) for approximately $90
Frog Toggs are pretty darn good also and can be found very inexpensively at times.
A couple fo thought i would like to leave you with. Buying a Jacket made to protect you from the elements, a rain jacket can be a decision that can save you from hours of discomfort and potentially save your life. That might sound drastic but is true. If i really could only spend 100 Bucks on my rain jacket i would probably buy the Marmot. BUT, i would much rather save and work a little overtime, take my lunch to work, skip eating out for a month or two, or three, to buy a higher quality piece of rain gear. Thats easy for me to say cause its not my money being spent.
Kuiu, Sitka Gear, Arc'teryx and many others, to name a few, have developed outerwear to protect us more effectively. These jacket are tougher, more water repellent, and last many more years than there less expensive counterparts.