I'm planning on ordering my new struts very soon and I'm a little undecided on springs. I dont want to leave the stockers in place since I'm having a bit of rear sag. I know a couple of you here have said that struts alone will solve the issue but I just cant go thru all the work of removing them and no giving myself some mental insurance. The lowering springs from ZZ are really my first choice since they are progressive and I believe will give a good ride. I'm just very concerned about when we take off on vacation with a trunk full of luggage. I checked AutoZone's website and saw that they offered replacement spring for coupe and sedan. What if Ijust kept the stock fronts and added a sedan spring out back?...that should level the car and buy me a little insurance for luggage.
Does anyone here have the lowering springs and carry stuff in your trunk without issue?

I know our cars like to squat once you add any weight in the rear seat or the trunk. After I installed my KYBs it didn't lift much, but after a few hundred miles it began to. But I wish I did install the stiffer springs that Blackarrow sent me that gmpartsdirect.com carries for around $100 a set. I may plan on changing them out sometime when I get ambitious again, but not necessary mod right now. I also got a nice combo Impact wrench kit, made it soo much easier. I got an air one but wish I got an electric one so it can be more portable. Good luck, and I don't have any advice on the lower springs, sorry.

my ride is alright does get a lil rough on larger bumbs... and i havent thrown in my subs in the trunk that should add at least 50 or 75 pounds ... so i dont know how much if any it will sag

I put the stiffest springs that are available for our cars (standard rates on front, stiffest)

and progressive rates on back (intrigue) and the car doesn't sag at all with approx 800lbs of DJ equipment in it. it actually sits just like stock ride height new. I also got AGXs and when it's empty it rides a bit stiffer than stock (when turned down), and when I'm loaded, I turn them up. only possible downside of the combo is when the car is empty, the car tends to sit about an inch higher in the rear than in the front. not noticable to anyone but a fellow GPer, though

I've got B&G's with a set of spring blockers on my car and don't normally have issues.

If you're going to lower though I'd suggest the Eibachs. Had a friend with them on his car without spring blockers and he didn't have any issues. The car actually rode really nicely too. I Kinda wish I had gone with the Eibachs.

I tried a set of Vogtlands at one point and didn't like them at all. Car rode too high and soft for my tastes.