Two years ago I went to AD to purchase 5712/a but was unavailable so end up buying 5711/a instead. Now I got a call from AD that I can purchase 5712/a right away. However, I was thinking of purchasing 5164 and was waiting for it to arrive. Dealer told me that I still have to wait for more than a month for 5164 to arrive and at that time 5712/a will probably be sold. Without seeing 5164 in person, I'm really having a hard time to decide since I can not see both at the same time. Can somebody give me a wise advise? Thank you ahead