I've just transferred to AAISP, and everything went flawlessly, with useful informative messages throughout. The only query was instantly responded to there and then on the phone.
So far, no problems with the line or setup.
Any issues with speed will be due to the line from me to the cabinet, not AAISP.
Not the cheapest, but provides features I would like and are keeping up to date (eg. IPv6 support out of the box).
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