I got a Garmin Rino 530 around Christmas time last year. I like it except that the signal drops of some under trees. Of course Garmin waits until after I buy one to introduce the "high sensitivity" model that I assume has the Sirf chip. I'm just wondering if it is worth the upgrade. It looks like the price for the 530 has gone down so I would only be able to get maybe around $200 for it on ebay. The new model goes for around $400. I don't want to eat $200, but I want it to work. Think it's worth it?