I was with Plusnet for 4 years now. Mostly we had a good experience, especially considering the low price. Now changing to Andrew & Arnolds (AA) because of a move and good service/reviews.
The initial setup was painful and took a lot longer than anticipated: The originally promised 3 weeks became 6 weeks in the end - not sure if their fault or BT/OpenReach.
Using ADSL2, speeds were not at the maximum 18 Mbit at the beginning, often only around 10, but over time the maximum speed got better and since a long time now is reliabily close to the top range. Important hint: Call Plusnet to unlock your upload, which lingered at 300kbit before I got the full 1Mbit, and blocked download speeds via overhead.
There have been not many outages, and if so mostly for a short period at night (unannounced maintenance?). Recently, there were a few weeks where router lost sync multiple times a day. After calling the support hotline, I changed a few advanced DSL settings on my FritzBox router and could fix the problem that way. Something in the copper wire must have gotten funny.
Support seems competent enough and very friendly, but the waiting times can be too long (last time more than 1 hour).
I liked about them that they never bothered to implement the government internet filter, and that they just informed me about copyright infrigment notifications without giving the requesting party any of my details or committing to any action on their side. A provider that is your friend, and not the big guy's one.
For the cheap price they did an alright job I think, certainly not perfect, but that is not expected. Was happy with them.
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