I have never had poor quality from summit. I've had nothing but good luck with them, great service, great shipping, fast delivery, nothing but good with them. I just ordered a bunch of things from them, one backordered, and it arrived before they said it'd be availible, they even sent a post card to me aying they were sorry it was taking a bit, and said if I didn't get it by the first of March they'd send another post card to see if I still wanted to wait or if I wanted a refund. The part came in that day though. I ordered it feb. 1 or 2, and knew it was listed as availible feb. 24 or so. I got it thursday. Their customer service is very helpful too. email replies are slow but I always get the answers I ned or I am looking for, phone is much faster. I ordered rings that would not fit my truck and had no idea why they would not, turns out they had deep oil grroves, shallow and medium, I got deep and needed shallow. Sent them back, got a refund and got my right ones pretty quick.
Nothing bad with jegs, only ordered from them a couple times, mostly deal with summit.
GREAT with rockauto. very fast, only dealt with them once, they messed up the order, sent me four of the same tie rod ends, instead of 2 inner and 2 outer, called them up, they sent me the right ones FREE, told me to keep the others and dispose of as I see fit. So i did, kept em in the box for a future square body front end.
Northern auto parts was good too, nothing bad to say on them. I ordered my gasket set, and cam kit from them for my 88. Turns out the timing set was double roller, so it was a nice surprise.
Jcwhitney has always been awesome, ordered from them alot, never a problem. Ordered a lift kit for dad's 86, hood scoops, alot of stuff.
streetsideauto.com was awesome too, I ordered my valve covers, air cleaner, stainless fender trim, stainless rocker trim, and I don't know what else from them. Great packaging to protect everything and very fast shipping. Only complaint, their search feature on their site is weird and doesn't work right. They price beat and match of course.
Amazon.com, we order everything from them, great to deal with, only had a book get messed up once, had a sticker on it to scan with a different name then what the book was, we ordered the book listed on the sticker, but the book wasn't it, sticker said it was lol. Sent it back no problems though and got a full refund. ordering certain car/truck parts, you need to know what part you need, their search isn't always right as to what fits and what doesn't. Their site sometimes says it won't fit the vehicle I want it for, other sites say it does or I know it will fit, other times it says it'll fit and don't, but only once, an egr valve and I didn't know you had to have the stock numbers first.
So with that said, I usually deal with summit and amazon the most. I always check prices with all of them including autozone and advanced, and whoever has the best price on them is who I go with.