Aim to reset service on my 14 Porsche Cayenne GTS(958), but it would be great if it read codes on my 996TT and my wife's C250 as well. What's the best value diagnostic tool? iCarScan? or Foxwell NT530 Porsche Scanner?
Schwaben is a Foxwell NT510 in a dark suit (the actual Foxwell one is red..) I'd suggest the Foxwell NT530 - ordered directly from them it's around $155 (if you ask nicely..) with the Porsche software. It won't at this time do everything a PIWIS will do on the 958, but software updates are free for life and I expect with time it's capabilities will grow. It is most excellent for the 987 series boxster/cayman, and the earlier 955/957 series Cayenne - in those cases it apparently can do just about anything the PIWIS does. Foxwell website in US: https://www.foxwelltool.com/ - delivery was quite fast for mine - 2 days.
I have the NT530 w/Porsche module (updated version of the 510) - and while it claims to do battery registration, and has all the necessary screens to do it, it simply doesn't work. iCarScan has an identical problem with the 958. If it doesn't work with the 530 it's not going to work with the 510.. and the difference between the 510 and 530 is the 510 had difficulty communicating over one of the computer buss' on late model BMWs. The 530 fixed that (according to the BMW forums.)