seem to be very accurate. On a recent fishing trip to a lake, I noticed the track the 522C was recording was off by at least 50ft, maybe more. I could be 20-30 feet from the bank and the track on the screen had me 20-30 feet on the bank. I I got to checking more of the landmarks and everything is quite a ways off. I switched to Lowrance Data (maps) and everything seemed to be very close to my actual position. This has been noticed on just one lake, but have only had it on two lakes. Never noticed it on the other lake. Any one seem this before? My version of Hotmaps is 2004.