Flying Age / Parenting Questions

Ok, this is a very odd situation. So my wife and her Ex had twin boys 5 years ago in December. He abandoned them in Florida when they were slightly over 1yo, and ran off with a girl he worked with to Indiana and they had a kid together. He did not keep in touch with them. Along I come; I meet them when they were near their 2nd birthday. We date for a couple months and they start calling me Dad, I think they are great kids and I didnt want to confuse them, so I let it go. We date and get married a few months after their 3rd b-day. I am the only dad they have ever known, I am a pretty good dad according to my wife and anyone that has seen them with me. So prior to their 4th b-day her Ex calls and said he would like to start visiting again. After the divorce in Jan of 06 he has child support taken out of his paycheck and was granted 1 weekend a month supervised visitation. So he visits once, then skips a few months and visits again, all of this is paid for by his mother and that he flyҒs for free as he works for an airline. So eventually they go to mediation in Feb of 08 on his second visit because he doesnt feel it is right that they are allowed to call me dad and he wants my now wife to force them to call me by my first name as well as other completely insane ideas. So they agree to some terms specifically about when he can visit, that he gets to call every week to talk to them and that after we visit his place in Aug of 08 we can try unsupervised visits at our place. So in Aug we move from VA to WA, he still lives in IN. Now that he has had an unsupervised visit he wants us to allow them to fly to him in IN. We adamantly refuse to allow this and said that wonҒt happen till they are at least 12. So he wants to fly from Louisville, KY to Seattle then fly back to KY with them then fly back to Seattle the next day and he would fly back to KY all in a weekend. He wants this to happen after 1 successful unsupervised visit. What Im asking is what is a reasonable time for them to allow them to fly with him to KY? BTW he only flyҒs stand by so he isnt even guaranteed a flight for him let alone him and the twins. Also he has never came on his designated weekend that he demanded in mediation, my wife has allowed him to come other times as to not warrant another mediation or more fights. He has never called them to talk to them ever in almost a year since the visits started. In 12 months he has made 7 visits all with his mom so she can pay for the expense of car and hotel. I have offered many times to adopt them. Personally our plan is that he can continue unsupervised for 6mo where they are picked up in the morning and returned at night, then 6 mo of unsupervised overnight for 1 night of a weekend near us in WA. Then 20 months from now after school letҒs out when they are 6.5yo they can get on a plane with him for a weeklong visit over summer vacation once a month and over Christmas vacation and alternate spring breaks. Never allowing them to fly out there over the weekend during the school year, never forcing them to miss their activities if they dont want to spend time with him, he is welcome to come and act like a parent at their events/practices/games. Does anyone think this is unreasonable? I love these boys like my own and now that we have another son together. The boys donҒt know he is their dad even though he tried to explain it to them. They insist on calling me daddy and him Ross no matter how he corrects them. Thanks Steve