Personally I abhor the platforms that Spreadbetting companies use. if you have no problem with that, then spreadbetting is something you should definitely consider.
I currently use spread betting for my FX trading for the simple reason all bets stop in base currency, so even if betting on crosses e.g EUR/JPY I don’t have to worry about other exchange rates. The platfom I use also allows me to trade FX 24hrs a day the same as normal platforms.
I must admit however that the charting software is not the best, but to offset that I also use other packages and feeds to ensure I have all the indicators I need and the price quoted is in line with the market. The only other downside is that the bet minimum is �1 per point (approx 1 mini contract) so if your new to trading or have a limited stake try low volatility pairs.
I regards to tax in the UK you don’t pay any income or CGT on profits made but equally cannot write off CGT losses either.