Everything is down to personal preference unless you're a religious
zealot. My personal take on valves is DIN, because they just have a
far more engineered feel and the O-rings don't seem to pop anything
like as often.

I like manifolds too as I can revert to independents just by closing
the knob but if one reg freeflows on me I can still get to all my
gas through the other. For the balance of probable faults the
manifold will get my sorry hide out of more, more easily.

But as we say it's your call.

nigelH

Hi Gary,

  Virtually any new 232b tank you buy will have a DIN hole that is
filled with a slug to convert it to A Clamp - hence you will be able to
use the valve immediately with an A clamp regulator, and when you have a
little spare cash and can change the reg to DIN you'll just unscrew the
slug and off you go.

Nigel has a particularly useful page here:

http://www.nigelhewitt.co.uk/diving/din.html

 If you want 300b you need to go DIN.

  cheers,

    Ben

You sort of have the questions in reverse order. If you decide to manifold
the tanks, then you'll be buying new valves anyway. That's part of what it
takes to manifold them.

As for being a matter of personal preference, sort of. It's also a matter of
safety.  While it's possible to dive independents safely, there are
advantages to diving them manifolded. The question is, are the advantages
worth the expense and inconvenience of having two of your tanks more or less
permanently attached to one another. My answer was yes. Yours may be
different.

I think the decision on whether to go with DIN or A clamp depends on how and
where you will be diving. If fill services and backup equipment are
available in A clamp and that's what you already have, go with A clamp.
While there's a slight reliability advantage to DIN, it's not enough to
spend a lot of money if you don't need to. Personally, I converted all my
tanks to 232 bar DIN valves with the conversion slugs. I can use them with
my DIN regulators, all of which are 300 bar, or with my A clamp regulators,
all of which are rated beyond the rated pressure of the tanks I use.
Replacing valves was cheaper than converting all my regulators and less
likely to run me into problems with my wife, who likes her regulators just
like they are, thank you very much.

Lee