Really no optical differences between the old EL and the new Fieldpro models of EL. In fact some members prefer the older model because they can use their own binocular straps on them instead of the Fieldpro straps although I hear with a special adaptor you can use your strap with the Fieldpro connectors. The Fieldpro also have integrated objective covers. Here is a whole thread on the subject.
Yes, I have seen those adaptors. But if you want to use your own strap anyway why pay an extra $800 for the updated Fieldpro model and then have to buy adaptors on top of it. I personally don't think the integrated objective covers are worth the difference in money. The old tethered ones work just fine.
I can highly recommend the Swarovision 10x50 EL's. I have the non-field pro model and I think they are best birding binoculars I have ever used in 10x. I think the Swarovsison 8x32 SV is the best 8x32 roof and the Habicht 8x30 W is the best 8x30 porro made.
