will work with my WP30? I know there are many models out there, but again, I come to this site for opinions. I want one that is not handheld, don't want to deal with replacing batteries all the time. I want one that has a display that can be read at night and day and has a decent size display. Color would be nice, but seems a bit costly right now. Would like the ability of adding chart or map details of spec. areas for close up detail charting. Mostly, I want it to connect and commincate with my WP-30. I want to save myself the trouble of trying the ones that don't work too well. Please include spec. model numbers with responses. Thanks in advance to all.