That's what I was thinking. Worst case, get these now and they work better than stock, but, say Steeda or MM, works better, just buy those later. I feel like anything is better than stock as far as suspension goes 
Apparently, looking at a similar kit from UPR, the kit comes with hardware for both 79-98 and 99-04 Mustangs.if the ad says "fit's all '79-'04, run the other way 'casue new edge cars use diffrent sized lower control arm bolt's. while the same lenght, '79-'98 lca's WILL NOT WORK on new edge cars, new edge lca's WILL WORK on'79-'98's if you drill the mounting holes bigger & use bigger (dia.) bolts.
I keep this Stang in a straight lineDo not change the uppers if you go with poly bushing lowers.
It will eat the bushing alive.
Especially if you do any open tracking.
You can get away with it with a Pan-hard bar sometimes.
Right on. I just emailed Blue Oval to see if they do include the hardware/sleeves w/ the kit and if not then I'm either getting the J&M or UPR kit.ocasionally they do sell kits that come with hardware/sleeves for both, the kit you had the link to (along with Summit's own brand & most ebay kits) only are for '79-'98's. getting back to the original question, I had J&M's on my car for a couple of years with no problems.
Oh ok I see what you're saying. I have heard that one before from other Mustang guys out this way. I will definitely keep an eye on them. Worst case get both then just go back to stock uppers.Keep your eyes on the bushings at the chassis end.
On the one Stang I went cheap on I ate bushings often.
After speaking to MM, Steeda, BBK and several others they all said the same thing.
Stock uppers are the best unless it is a Drag only car.
The big stock rubber bushings help keep The lowers from binding.
That's a great read. See the only corners the car sees is daily driving turns which aren't aggressive and I love going to the strip to open her up. I will definitely keep my eye on those uppers though.Replacement bushing are cheap. lol
PITA is changing them though.
Have you ever read this?
Late Model Mustang Suspension Basics