I'm not one to do unnecessary work, that's the only reason I've waited until 95,000 miles to install the Vogtland springs. I wanted to replace most of my suspension components at around 100,000 miles, so I may as well install new springs at that time. I found a deal on an ACDelco front passenger strut for the Buick Regal, so I decided to go with Buick Regal spec suspension all around. Struts are 506-1139/1140 and shocks are 560-846/847. I wanted to pre-assemble the struts, so I ordered KYB SM5872 (mounts) SB103 (bellows) SM5807 (insulators) and GM Genuine 11569637 (lock nuts) 13502405 (washers). Assembly was super easy, I got the lock nut on with my body weight compressing the spring. I also used GM Genuine 90538496 and 13330714 rear spring insulators, Ultra-Power K750660 and API 2700426001 sway bar links, GM Genuine 13281790 rear sway bar bushings, EBC UD1421 front brake pads, and Autoshack ASCA62728 (lower control arms) R65186PR (front rotors) HB613290PR (front wheel hubs).
It was a 3 afternoon job for me, everything was pretty straightforward. I don't recommend anyone to replace the rear sway bar bushings, it was more trouble than it was worth. I may start looking for shorter sway bar end links, if I find some I'll post the part numbers. Front hubs require a good swivel joint, 3/8 drive worked best for me.
I never liked the way the OEM brake pads felt, they gave me a bit of a false sense of security. They had a lot of initial bite, but I couldn't really modulate the pedal, it was sort of like an on/off switch. I overheated them once and after that they were dangerous. I found the EBC Ultimax pads on sale for $22.46 shipped, so I gave them a shot. I love the way they feel, very progressive and I've never had to use all of the pedal (I don't like the feeling of running out of pedal). They do create a lot of dust, but I don't care, I use a spray wax on my wheels every wash and it wipes off easily. I went with off brand rotors and hubs, the fit was fine, nothing good or bad to say.
In my opinion, our suspension is pretty darn good from the factory. I enjoy a spirited drive down a twisty narrow road with many potholes. I keep to my lane, which means I do hit a few potholes mid corner, but the chassis stays planted regardless of the terrain (For reference, this is with 215/60r16 Continental True Contact tires). After installing the Vogtland springs and 225/50r16 Falken Pro G5 Sport A/S, I only had a few chances to drive that backroad, but I noticed almost immediately the increased grip from the tires/suspension. Before the car felt lively, it would move around a bit and I'd have to make small adjustments. Now it just goes where I point with no regard for anything else, I can feel the bumps but they don't phase the chassis. When driving around town or on the freeway it doesn't feel much different than stock, other than occasional bottoming out on speed bumps and sharp inclines/declines. I'll be driving in snow next week, I don't have high hopes with this lack of ground clearance and sipes.