Using it on Three - Had it for a week and absolutely love it.
Couple of downsides - Email - I'm using IMAP to push my home account through and it works intermittently. I can still pick up my emails via webmail.
Other one is that when it tries to connect to the net (Seesmic refresh) when it's out of range i.e. in a tunnel it won't let me access the net. I have to force it to accept Three as my home network.
I suppose that's the problem of using an unsupported phone.
I really hope Acer roll out 2.0 at least and as soon as possible.
It's a really great phone.