Cantor
I have been using Cantor for spread betting for a few months now in addition to
IG.
I really like the ability to trade live on-line which is so much quicker than the telephone when you are short -term trading.
Have had a few problems with the live link from time to time and the site is a bit slow and fussy to load the live trading screen.
Also their spreads on some contracts are wider than
IG so there is a bit of a trade off between speed and spread but I find I use them much more than I thought I would.