The IST - it's a great little light - tight beam and very, very bright. Can signal people 1-2 meters away during shallow mid-day dives, and further when at depth. I ordered mine with 5 modes but will cut it down to two at some point (full and dim).
Great to hear from you by the way! I have had this nagging 'Oi - You haven't posted on scubaboard for a bloody long time' message up the top of the page every time I've logged in for the last few weeks
(months), so I'm glad to be able to say high (and get rid of that message).
Cheers,
Rohan.