Try and find one with a good chipset (e.g. SiRF Star III is great, I think there are other good ones now as well but I don't have the names). There are lots of cheap ebay receivers that claim to perform well but their chipsets are actually rubbish which results in a poor GPS fix.
I have an i-BLUE747 on order that should arrive on Thursday.
I bought it because it also logs data when not connected to an external device for later playback which I thought would be useful for hiking/biking when I knew where I was going but wanted to record it later on a map or to check out my mileage. There are a few that do this and they don't cost a lot more.
I researched here and a couple of other places before buying but will not have a good knowledge of how good my decision was until I have had time to use it.
Try and find one with a good chipset (e.g. SiRF Star III is great, I think there are other good ones now as well but I don't have the names). There are lots of cheap ebay receivers that claim to perform well but their chipsets are actually rubbish which results in a poor GPS fix.
I use a Holux GPSlim236 and it works really well.
Don't forget you will need software too.
Aside from the sw, is there anything else needed for the Axim X51V to work with BT GPS (i.e. addition HW)??