The only reason i'm not in camp 2 is because i'm not having the accuracy problems you're having. My 1st convert functions well enough and it exhibits none of the behavour you and others are reporting. It seems to me that there may be gps receiver hw differences in the 37x0 productions which it's native fw allows for, but the 34x0 fw either barely copes with [i.e. mine and Caty's and some others] and other hw where it doesn't work well at all [i.e. yours and others].
I can confirm that info by Caty. After converting and reconverting many times, my 1st 3790 returns to reporting 3m precision. NV cleared both before and after conversion/reconversion each time. I haven't yet reconverted the 2nd 3790 [3490_kunix] to find out.
In fairness, although any comparison is welcome you will probably only show that a 37>34 lacks accuracy compared to any other unit. My old SP 2610 is better than 37>34 anecdotally. All my other units show better precision than 37>34 converts do i.e. 13x0/14x0/1690/2455 etc. I've also done informal tests with 2460 as original and converted to dezl 560 which reports mostly 3m both ways. Also 255/265 converted to 465 doesn't suffer any accuracy loss by casual observation, nor does 40/50 > 42/52. The 37>34 is different. The other 3 conversions will both flash and work equally well with original boot.bin or with the full fw flashed. The 37x0 won't flash using original boot.bin but will flash full 34x0 fw. Whatthe! Weird hey? You bet it is, and my layman's guess is that's simply because the 3790 and 3490 are not completely identical physical hardware. So flashing a 37 to 34 is like trying a kid's pony saddle out on a racehorse, you might get it to go on but it won't work property.37xx -->34xx and other Nuvis comparison tests are welcomePut them off road.
Well, i still have one virgin 3790 [original & never converted] and 2 x 37>34. The only question is will i do the city test run with the 3490_kunix as 3490_kunix#2, as 3490 with unaltered 34x0 fw, or as 3790.More interesting should be to know if someone has two 37xx to compare,may be one provided by a friend: one 37xx original and a 37xx/34xx.
Suggestions are welcome, but if kunix comes up with another fw mod that's what i'll be using regardless [if it doesn't brick it of course].
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