The issue isn't as simple as that. For DIN, there are two types,
Firstly, there is the 5 thread 232 Bar (3000 PSI) that is now somewhat outdated. Fundamentally, any reg on the market now is capably of handling this.
However, there is also the 7 thread 300 Bar (4500 PSI) DIN fitting. A 7 thread DIN regulator will go into a 5 thread DIN Tank without a problem, however, due to the size difference, a 5 thread regulator, although it will physically go into a 7 thread tank valve, it will not touch the bottom, and the o-ring won't seal, and hence it is unusable. This is to avoid putting a 232 Bar regulator on a 300 Bar supply. This is by far the more common fitting available at the moment.
Now, In general 5 thread (232 Bar /300 PSI) DIN valves come with an insert to let you put a yoke over the (DIN) valve and seal everything up nicely.
7 thread DIN valves have never been sold as convertible. A lot of them are designed so that even if you make the insert yourself the voke physically won't go over the tank yalve.
However, when you go the other way - DIN regulator to Yoke style tank valve, you screw a yoke adapter onto the DIN regulator, giving you a yoke regulator. The adaptor works on either 5 or 7 thread DIN, (since both are for 232 Bar OR higher), and the tank valve if for upto 232 Bar, so any DIN reg. will go on any Yoke tank.
Now, why did I start off like this?
Simple, most regulators now sold as DIN, are sold as 7 thread 300 Bar / 4500 PSI (although some are still 5 thread), so, If you get a 7 thread DIN regulator, you can use it on any tank valve anywhere in the world.
However, if you have your own tanks etc... and you are staying with low pressure (3000 PSI /232 Bar) equipment, there is no real nead to spend the money on convertors / DIN regs, stay A-Clamp (Yoke). (But of course having said that, if the DIN + convertor is the same price as an A-clamp then go DIN)