From my experience, yes. Unless you get a 5-link, you may still experience wheel hop when removing the quads....even with the best upper and lower control arms and shocks. The problem isn't the adjustability or the flex of stock arms, it is due to the geometry of the rear suspension. The uppers are too close to the center to keep the rear axle from dancing up and down unevenly.
There are a TON of opinions out there, and every Mustang is different. You can take two Foxes with the same exact suspension setup, remove the quads and each car can react differently. Some people have no problems, others do. From my experience and judging from the opinions of others, it seems that more people suffer wheel hop than those who do not.
It's up to you, go with that setup and if you get wheel hop put the quads back on.
The quads are secondary shocks....which is a misnomer. They really don't work as shocks in the traditional sense. The control arms move laterally up and down and keep the axle "centered", while the shocks/springs dampen the upward and downward movement. However that alone does nothing to keep the ends of axle from moving up and towards the front of the car opposite of each other. That is where the quads come into play, they aren't really "shocks" as much as they are dampers, helping keep the axle from dancing thus keeping the wheels from hopping.
Let me just say this. I have Steeda tubular control arms, urethane bushings, Strange adjustable shocks, and full length subframe connectors. I did some modifications just to keep the quads. I had to make spacers and longer bolts for the frame brackets to space my quads away from shocks, yet still keep them away from the 275s I have in the back. Even with good suspension pieces, I still did everything I could to keep my quads. I wouldn't get rid of them...I have seen too many people with better suspension setups than mine experience wheel hop.
Got pics showing how you modified your quads?
No, I never remember to bring my camera to work with me.
It is pretty easy though. My problem was that I flipped my quads to fit my 275s in the rear, but the quads were riding against the shield on my Strange adjustable shocks.
I unbolted the quad shock from the frame mount, and unbolted the frame mount itself. I pressed out the quad shock bolt from the mount and got a new bolt/nut combo that was about an inch longer than the stock bolt, and the same thickness. The key is making sure the head of the bolt is thick enough that when resting in the hole in the bracket that the head sticks out slightly...just ever so slightly. That way when you bolt the bracket back to the frame, the thickness of the bolt head is such that it is pressed up against the frame (the head of the bolt sticking out of the back of the frame mount). By it pressing up against the frame when the bracket is bolted up, it keeps the mount bolt from spinning when you tighten the quad shock retainer nut.
With the bracket re-mounted back on the frame with the longer bolt, I used a .5" spacer on the bolt, then put the quad back on and tightened it down. You can use a stack of washers or a large nut as a spacer, I just happened to have a set of spacers sitting around. Now everything is spaced out and I have no issues with anything coming into contact with anything else.
I just installed 275 MT DR on the back of mine and just noticed that the quad shock is rubbing slightly. Should I just leave it rubbing or is there a way to modify it slightly? I do not want to remove them completely. I drive the car about 6K miles/yr and like I said it only rubs slightly. Once in a while i can smell hot rubber but other than that I didn't even notice.