The RGBA option has a number of adherents here on the board but, as Rapine says, it doesn't do white well - a decent approximation is something like this:
That's an RGB hilt with all three lit up - the pinkish tinge isn't quite so evident in real life, but it's a pinkish off-white.
I go for RGBW myself - like you, I like a white blade (indeed, my Lost Grey's blade is tri-cree silver).
Shipping to the UK will likely be about $50/£40. No way around that, sadly. It'll take about 4-5 days to be with you on average - sometimes you can get lucky and shipping will occur over the weekend, which speeds things along. Sometimes it lands at the airport on Friday night and sits there until the following week
Customs charges will be about £10-15 on top. FedEx sometimes cover that themselves, sometimes put it direct on your credit card and sometimes send you an invoice. No way of predicting which it'll be, based on my purchases over the last year or so.
You look like you'll have a great 'sabre there. If it's your first order, one thing to be aware of is that the Fulcrum is pretty thick, so if you have smaller hands it may not be as comfortable to hold. If you're after more of a display piece, on the other hand, it will look fantastic
