After a couple of months using the Wingle I am very happy with its performance. Browsing is as good as I need, and there have been very few times when it has slowed down enough to be noticeable.
I am using a contract sim, monthly rolling credit, no forward commitment, can cancel at any time. The data budget of 10GB per month is acceptable, 330MB a day is plenty of surfing, though one has to be careful with downloads and videos.
I went a bit over and found the over-run very expensive. But I swapped for a payg sim, topped up on line, and saved money.
Normal cost fifteen pounds for 10GB, 1.50/GB.
Over-run one pound for each ten megs, 100.00/GB.
Payg sim ten pounds for 1GB, 10.00/GB.