I believe the v5 is a Nooelec and is comparable to the RTL v3. The RTL v4 is the latest chip. They both have different strengths and weaknesses tho.
https://www.onesdr.com/rtl-sdr-vs-nesdr-which-one-should-i-b...
https://www.onesdr.com/rtl-sdr-vs-nesdr-which-one-should-i-b...
I'm looking at a bladeRF...