like you i too was getting frustrated with the VG+, i originally had the first VG and upgraded to the VG+ hoping the new display and processor in them would improve things. it did speed things up but the vehicle software updates they put out came with more bugs, and sometimes you have to revert back to the older versions and is just time consuming when u just want to get in there and the darn thing doesn't communicate with the ecu, so there u are checking if its your scanner that has the problem or the car. the VG has a 40GB Hard drive but really all the important software is on a 32MB internal memory yes
32MB! and its sad to say that it now can not save all the manufacturers in there at one time. I'm sure you know what to do in that case. if u look at the Nex-tek website they now release a VG+ 64 which i'm assuming is a 64MB version. my update for the VG is due for renewal but i don't think i will be needing it since i got the Gscan.
the only thing i like about the VG+ is the scope and simul-scan, being able to send a voltage, pulse through the sensor signal wire and reading it in the live data to confirm wiring is fine instead of removing/back probing the ecu and checking the pins.
another thing about the VG+, what ever you do, never use the service reset feature for a VX commodore as it will stuff up the instrument cluster speedo, and the speed sensor pulse would need to be reprogrammed for correct calibration or get a new instrument cluster so do it manually. ASS will never admit that it is the scanners fault, but it is. i'm not sure if they have speedo correction added yet (hardly use VG now), but the gscan can do it.
now about the Gscan, its one fast unit. you will notice this as soon as you turn it on unlike the carmanscan when loading. you have a simple menu layout, and when doing diagnosis on the same car its very handy to have the previous vehicle button instead of going through all the drop down menus again. i would have to say this is the best for asian cars including those imports that show up. as for KIA and Hyundai the software is OE same as dealer so the user interface is different from the rest of the manufacturers, not hard to follow once you use it a few times.
its also great for holdens, as now you can link second hand ecu for the VZ onwards. i recently change the ecu for a 2002 nissan N16 pulsar, brand new unit would cost $2000, picked one up from the wreckers for $100, the fella wanted to sell me the whole thing with keys and immobiliser warning me its not going to work without it. we did the job with the pin number shown for programming mode whereas the VG would have made you get it from the dealer
you can do a system scan to check the different modules that are present and number of DTC in there.
so to sum up, the only time i bring out the carman VG is when i need to use the scope to look at ignition, sensor patterns or simulate a sensor. but the Gscan is the first tool i would pull out when doing any diagnosis or programming. i haven't had any bad experience with it yet so hope that helps.