Mike, here's the deal...
Asking the question of which is best of the two choices you've made, you're going to have the inherent conflict of people using one or the other. Each group will swear by the results of their choice. Perhaps the only useful replies will be by someone that has both installed and has the ability to do side-by-side comparisons on signals within their reach. When I went from an indoor antenna to a Diamond Discone and the world suddenly opened up, I'll tell you that's a great antenna choice. So will the guy under the same circumstances that installed the Scantenna.
Nathan (Dispatcher 308) on our home board co-phased a pair of Scantennas and swears by them. He did that because he found (and I've heard many others state) the Scantenna tends to be a bit directional. So he has one facing north/south and the other east/west. Who knows if that's a good idea or bad? He'll tell you it's fantastic.
You've heard what I can do with my discone but the same antenna on your roof may not do as well. The fact that I regularly hear out to 100 miles on VHF doesn't mean a thing when it's plunked down in your location, even though we're fairly near each other. I understand why you can't take into consideration all the technical antenna knowledge that's out there. It's too simple a problem to put yourself though that song and dance routine when you're not schooled in that discipline nor inclined to spend the next six months studying the problem.
You have 100 bucks to spend. Well, $130 will get you both the Diamond Discone and the Scantenna. Hell, throw both of them in the air. Keep the one that works the best, put the other in the For Sale thread, get half your money back. You'll then have tried both for under your $100 limit. Most importantly, it will answer your basic question of which is best for your listening interests and works best in your specific location. Occam's Razor (the best solution is most often the more simple of the choices.)
[Edit]
P.S. It's 13:40, middle of the day, and I'm currently listening to FDNY Brooklyn borough on 154.37 [PL186.2] so that makes the Diamond Discone a fantastic antenna choice, no? No, because I don't know if the Scantenna would be receiving it even better.
Alan
