Those are nifty. It has been quite a while since I’ve been in tune with that stream of devices, but here’s what I remember (this may have changed, but that industry tends to change very slowly):
it SAYS it covers 1980+ domestic, 1983+ asian, and that European vehicles are optional (even though it states it covers 1992+). That was NOT the case, per se. They usually worked with OBD vehicles in those ranges, and generic OBDII. Manufacturer specific modules were $(domestic)-$$$$(European). Subscriptions were the rage, so you needed to have them in place, or pay the back fees when/if you wanted to upgrade or add on. This has now become the norm in most realms of “computer stuff”, so I reckon it has progressed and pervaded further into this space as well. Thus, in addition to the purchase, you’ll have a maintenance fee (per month, per year, etc.)
You are correct virtually every shop has one, but this is, in part, because they NEED it if they want to remain viable in today’s market. As we are not a seller of service, it’s less compelling for us.
Also, as far as I can tell, this does not include such capabilities as reprogramming (keys, settable features such as door unlock functions from the FOB, etc.) or “flashing” (upgrades to software, such as transmission re-coding, engine controller recoding, etc.), which are the drive behind the aftermarket devices to end users for specific makes/models/etc. as mentioned in the other thread.
Further, to use full capabilities, you’ll need to (purchase, I presume) obtain the SnapOn ShopStreamConnect software (and have it installed somewhere, which they usually like to sell you as well).
Having said all that, and this: I reckon you’ll be disappointed by what you think you’ll be able to do vs. what you actually CAN do, I say go for it. They are neat devices.