Most importantly, it looks like they offer a scan to confirm the proper upgrade for your specific model. (it's not out of stock, btw.) Except you get a couple extra goodies like an USB 3.0 enclosure for the drive you replace, tools, replacement guide, screws, rubber feet, etc. I recommend checking out Transcend's JetDrive since it's a comparable price to the ifixit link. Which means it's going to be more expensive off the bat since it's not in 'high' demand and even more so since the seller probably knows it's intended for a MacBook.

The only way to upgrade your MacBook (or more recent ones) is to buy an uncommon PCIe x2 SSD. That being said, a simple answer to your question is, no. We are talking about an Apple product though and it goes without saying that nothing is going to be standard or easy. Many ultrabooks use this connection and you can easily buy adapters for regular laptops. MSATA's are incredibly universal and on par with the standard SSD pricing. The recent ones don't have the 'easy' mSATA upgrade. I can personally confirm this info since I've worked on several dozen (retail returned) MacBooks over the past year and a half.

This likely being the 'easy upgrade' you mentioned. MacBook Pro's haven't had a standard mSATA connection since 2013.

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