Allianz are the way to go, They put it down proper as a DC5 type R and the quotes are reasonable too,
Axa aren't too bad either, The rest of them are pure pants when it comes to quoting the DC5!
ARC are back trading a good few months, RHDjapan also supply the box and replacement filters,
http://www.rhdjapan.com/arc-super-induction-box-dc5-fd3s.html
I had Works one's before,didn't find them great at all, They were way too soft and i didn't trust the threading either,
I have Muteki sr48's on now for the last year or more and they're still like new and i've had the wheels on and off a few times,
I think they're made from lightweight...