I have mixed views of VM, I dont think they are a outright disaster but it is a risky move.
When you are not suffering noticeable congestion then the service is decent.
Benefits I would say are.
Guaranteed connection speed - it either connects at the package speed or does not connect at all. No distance and line quality bullcrap.
Exit points of their network nationwide so e.g. connecting to steam manchester servers should not need to go to london first.
No DLM type profiles, so not having to deal with things like excessive interleaving delay.
They hand out discounts really easily if there is problems, if you the sort of person who is fine with a cheap service even if problematic then this can be a good thing.
The CPE supports modem mode, VM is probably the only UK provider who recognises that there is a benefit for a modem mode on their equipment. Funny enough I pride myself on getting modem mode added, as it all started when I mentioned it to a senior VM CS bod on his blog several years ago.
If they need to send out an engineer, it comes quickly and is no threat of fee's.
Phone line's are in my experience much better quality than openreach, but my experience is based on having a long copper length to exchange.
Services are typically completely unaffected by the weather unlike satellite and DSL.
They have try before you commit policy.
VM have problematic areas, the amount of areas 'seems' to have increased following their vivid product launches, history tends to show once the area has capacity problems in tends to be long term with possible short bursts of time with good service. Fix dates are frequently months away and when they do arrive get pushed back more often than not, if a fix is applied it is often not good enough.
They continue to sell to areas that are even confirmed as saturated by their own network team, which is one of the reasons people dont have respect for VM over this issue. I dont mean just accepting orders, but I mean carrying out aggressive sales tactics like leaflets through doors.
They allow people to upgrade early to new products before any infrastructure changes have occurred and even in saturated areas.
India tech support.