I'm currently gathering all the parts for a suspension overhaul on my 99 coupe. I've already acquired C5Z front and rear leaf springs (lowering bolt is seized and stripped in the front spring, any suggestions?) and the rest of the parts I will add will be DRM Bilstein custom valved shocks and C6 z51 front and rear sway bars.
My question is what are good end links to use? I know the stock plastic ones suck but I couldn't find a consensus on a good brand to go with for the end links. I also would like to do my bushings while I'm in there, along with lowering bolts. So my question is what do y'all suggest with regards to end links, suspension bushings, and lowering bolts. Also what can I do to get out the stripped (head stripped not the threads) and seized lowering bolt currently in the front.

 

Agreed, assuming that they are still available, stay far away from the plastic drive links. I could be wrong, but I don't think that there is any one particular brand of anti-sway bar drive link that is "the one." That said, I'd resist the urge to hop onto Amazon searching for a bargain out of China. Instead, I'd go to to a "serious" site like DRM, or LG Motorsports, for example and get whichever adjustable links that they have on offer.

There are several options for bushings: the squishy OE rubber bushings, polyurethane bushings, delrin bushings, or spherical bearings.
You already know about the squishy variety.
Urethane bushings tend to have noise (squeaking) issues, unless they are carefully assembled. They also tend to require periodic lubrication from time to time. Some manufacturers claim to have solved the noise problems with a graphite infused urethane material.
There are a couple sources for Teflon infused Delrin bushings that tend not to suffer from the noise tendencies of urethane and tend to require much less maintenance.
Spherical bearings are typically only used on the track, but some who enjoy particularly smooth roads also run them on the street.

You will typically find either Delrin bushings, or spherical bearings on race cars, depending on budgets and class rules.

For anti-roll bar bushings, you can pretty much only choose from squishy OE rubber, or urethane, as there does not seem to be a great variety of bar diameters supported in Delrin.

I've run polyurethane on the street and even with crummy roads, I didn't find them to be harsh in any way. If I had it to do over again, I'd probably go with Delrin. Obviously, everyone (and the roads in question) is different, so YMMV.