I have two dongles: An OBDLinkMX+ for general use and a VCXNano for Techstream. Both were $100 when I bought them. The OBDLink is great for general diagnosis and lets me read all my modules except SRS. I can setup data monitoring on my phone or pair it to a headunit really easy while having some of the highest data transfer speeds of most dongles I could find. BlueDriver & Veepeak were close contenders but I am happy with my purchase.

The VCXNano is great for Techstream because its wired or wireless connection and if I spent a little more I could get a universal multi vendor dongle. I originally ran it with an older Lenovo Thinkpad but recently loaded the VXDiag Suite to my surface tablet and its a way better experience or at least as much as it can be with TS. Getting TS up and running was a bit tricky but it sure beats using the cheaper dongles and cables everyone recommended to me before with 15 year old versions of TS.