Grumbling aside, Amazon’s Prime Day hits milestone

When Amazon announced some of the deals that would be offered starting at midnight Wednesday—from $75 TVs to half-off cameras—Amazon Prime members set their alarms for the price savings.

And while many online shoppers, including those opting to check out Wal-Mart's competing promotion, encountered slow load times, Amazon still managed to top peak order rates seen during last year's Black Friday. (Tweet This)

Even by noon, Amazon's third party U.S. same-store sales for July 15 were about 80 percent ahead of where they were at that point last year, according to e-commerce sales tracker ChannelAdvisor. By the end of the day, ChannelAdvisor CEO Scot Wingo said he could see that number swelling to 100 percent, marking a growth rate of about four times the average clip seen so far on the year.

But just because shoppers came in waves bigger than Black Friday that didn't mean they all thought the day's deals lived up to the Black Friday-busting hype.

Even bargains on high-profile items like Amazon's Fire TV Stick lasted only a couple of hours before the savings were fully claimed. The waitlist for the TV streaming device filled minutes later, leading some frustrated customers to wonder if they were intentionally misled.

In total Amazon saw social mentions jump by about 50 percent compared to its 30-day average, according to Adobe Digital Index data. However, the majority of the sentiment behind those Amazon Prime Day mentions overwhelmingly related to "sadness," with much of the disappointment stemming from a lack of blockbuster items.

Amazon insisted it was part of a plan to "stagger the deals to make sure the fun will last through tonight," according to a spokeswoman. With new deals starting as often as every 10 minutes, she urged Prime customers to stay tuned for more—and stay tuned they did. By the afternoon shoppers had bought up 28,000 Rubbermaid sets, 35,000 Lord of the Rings Blu-Ray sets, and battled over a Kate Spade purse deal that was gone in less than a minute.

But when traffic from shoppers flooding both Wal-Mart and Amazon surged, some added slow load times to their growing list of complaints.

Data from Internet performance firm Catchpoint Systems revealed Wal-Mart suffered greater interruptions with more widespread outages and slower reported performance than its online competitor. Perhaps due to its prepared efforts right before midnight, Amazon only briefly saw its load times nearly double before its issues were resolved in the afternoon.

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But even with those slow load times the fact customers are flocking to the site bodes well for Amazon, according to Morningstar Senior Analyst R.J. Hottovy.

"You're going to hear some complaints about it, but people still carry on in this treasure hunt," he said. "The limited supply of these deals has some people going and even buying items later at full price."

Though the jump in third party same store sales is indicative of a successful promotion, investors will have to wait until Amazon's quarterly earnings for the full sales picture and to see just how big of an impact Prime Day had on first party sales.