Which do you think is best?
I think both are very handsome! I prefer [name]Theo[/name] [name]Alastair[/name]/[name]Alistair[/name] because it’s the less common option but I think either would be great!
While I prefer [name]William[/name] in general, I like [name]Alistair[/name] better as a MN for [name]Theo[/name]. 
[name]Theo[/name] [name]Alistair[/name] is great!
Good luck!
I prefer [name]Theo[/name] [name]Alastair[/name]. I like its spunky vibe. [name]William[/name] is a fine name but it’s never been a favourite of mine.
[name]Both[/name] are very handsome! I’m leaning toward [name]Theo[/name] [name]Alastair[/name], though. I don’t think you could go wrong with either of them, honestly. Well done and best wishes!
I am in the minority, I prefer [name]Theo[/name] [name]William[/name].
Another vote for [name]Theo[/name] [name]Alistair[/name] from me - and I prefer this spelling, too.
I love both but prefer [name]Alastair[/name] with [name]Theo[/name].
[name]Alastair[/name] ! Or alistar but [name]William[/name] sounds great
[name]Theo[/name] [name]Alastair[/name] is such a gorgeous name!
I’d pick [name]William[/name], but either is a great choice. [name]Alistair[/name] just seems a tad too upidity for me fun [name]Theo[/name].
love [name]Alistair[/name]!