I explained my doubts in an earlier reply, you must have missed it. I'm sorry to say I think it's rather lazy to dismiss people as "just determined to find fault with anything he sats [sic] or does, just because." People have clearly and repeatedly explained precisely why there are concerns, and you have failed to address them. Which is of course your right - but I feel it is disingenuous to claim you believe criticism is unfounded. You may like him and trust him, but you can presumably understand why others are sceptical, and claiming they have absolutely no reason to be and that everybody's just pretending to be worried when they really actually know there's nothing to worry about is a bit silly.
While you may indeed think it makes perfect sense for him to base the devolution office where it has been 'most successful', that does not explain what other options were considered on the way to this decision. One would expect such a large, expensive decision to at the very least require some discussion of alternative options, and yet this seems to have been a choice he made entirely on his own. And even he's not claiming it's because it's where devolution has been most successful, that's just your interpretation. I believe I am not alone in thinking it's purely because that's where he's from, rather than from any analytical calculation of where it would be best placed. I would love to be proven wrong, as it's obviously terrifying to confront the notion of having a prime minister who would do something like that. I'm very surprised if you can't see why people are worried.
I personally think it makes far more sense to place it somewhere more central, with excellent transport link, and in desperate need of the magic he brought to Manchester. Then he can demonstrate Manchesterism can work anywhere, and silence his doubters. I would have thought he'd jump at the chance. Now, you may disagree obviously, but I'm sure you can accept that is a perfectly valid idea, and I am very curious as to why he discounted it when he was debating the location. I'm also fascinated to know where else was considered, and I doubt I'm alone.
Hopefully he'll soon reassure everybody and release details of the consultations and analysis that's been undertaken.