Just a heads up for anyone planning to buy the Ultimate immersion set with the Arc Ultra. 
This is on sale for £2426. There is also a 25% discount until 3 March - but not on anything to do with the arc unfortunately. 
However, if you’ve got any trade in products then buy the Era 300 x 2 and the sub 4 with your 25% discount and make a separate order for the Arc (on which you’ll get your 15% trade in discount) and this will come to £2121.90 - an extra saving of just over £300