I'm pretty much convinced that one will never have a problem with a Super Speed . . . any variety!! I tried out a well-worn user-grade Red Tip that I picked up in a lot recently and it worked great! Next in my rotation was my Slim . . . wouldn't you know this week I went right back to that Red Tip and am shaving closer than ever with zero irritation!
The Red Tip is not inherently aggressive and should not be feared . . . it does, however, perform best with zero pressure or less . . . push the RT and you'll get irritation for sure! But, you should be getting an irritation-free shave with a regular SS ('40s or flare) or a DE89 . . . so I'd have to suspect technique or prep as part of the problem below the jaw line and not just your razor.