I'm sorry I don't mean that make you feel bad 
This is how I think of it ( just my opinion of course )
Right now you are still trying to get all the information to decide if he's the right child for you. So you need to focus on that issue - what are his needs, can you meet them, what are the implications of these needs for you, your job, your marriage, your family, your Lifestyle. Talking with FC is your best source of this information , she lives with him 24/7.
Once you have got this information ( as much as you can get ) , you and DP neee to discuss it all. Have a very, very tough talk and be very honest with each other.
Then you can decide to go for it. There will be plenty time during introduction to ask about bubbles vs non bubbles. Or he's 5, you can ask him.
It's too easy to get seduced into all the nice and fun bits of parenting ( decorating his room, buying cute clothes and toys ) before you have done the hard thinking about how this is going to work for you all.
So, will he every be able to cope with childcare?
If not, who is going to give up work / go part time and for how long ? One of both of you ?
How will this affect your savings and pensions?
What about the one who works full time - how will they feel about that ?
What about your career in the longer term?
how will it affect your social life and hobbies if this child can't cope with the things you do ?
How will you cope with the reaction of friends and family ? Many are cool with a baby , less so with a ready made child.
Will he be able to attend a mainstream secondary school and if not what are the options in your area ?
Does he nee any medical input and what is there locally ?
Does your relationships have the resilience to cope with this lads needs ? ( im thinking of the thread here where an newly adoptive father was whining that he didn't get enough " couple time" )
What will it REALLY be like to live with any behaviours he has?
How would it be if you were never able to change them and he was always like that ?
I know you have thought through these issues in general but it's very different when you have the needs of a specific child right in front of you.
I'm sorry , I know I sound like a hard cow and you are not buying a house. But many adopted children have a lot of needs and many adoptive couples split up over it, so make sure you are 100% agreed on this.