members here had some luck with the Dynavin... have you checked into it? do a search on the forum for some better units - it seems that only review for the Sino gave it a 3 out of 5... believe me, at $500 you should be able to find something relatively decent... that HU is probably plug-n-play for a non-DSP models but the internal embedded software might be flaky... and on top of that, the description talks about a license plate light camera being inclulded - i did not see the camera on the picture of the accessories, and on top of that, those license plate camaeras do NOT fit the E53 license plate light opening... several folks run into that camera issue...

keep on reading - i personally prefer factory nav, even though it is already outdated... it is just integrated better into the car... but, if you are replacing the non-nav system, i can see going with aftermarket HU - make sure that the bezel/shroud fits well and be skeptical of the sellers' claims...

That Sino model is lesse known... check houligan and the dynavin... there are comparasions going on about the two...

also, have you seen this thread? http://www.xoutpost.com/bmw-sav-foru...-headunit.html