Keep your MK25

I recently got a set of new MK25s although I could go with HOGs

.. Joking ... I just did not want to get another diaphragm reg...
I was looking at HOGs and a minor inconvenience I saw was that the low pressure side (the one with the diaphragm) protrudes too far just as on Apekses and other regs of the same design slightly interfering with the access to the valve knobs.
Those who have them say it's not an issue though...
MK25s does not have that as the DIN connector is located almost at the end of body.
I recently put a question on this forum as well as the others regarding the lowest temps that MK25 can handle and I saw many replies from people saying they were using them as low as 37f in fresh water.
There were few people from California as well saying they are working very well. I'm yet to test my set though.
Speaking about the support it can be tricky even in Canada. My LDS that services Apekses, Scubapros, Zeagles Mares etc. and have parts for them has never seen HOGs.
So if you travel a lot and care about the support you either have to stick with SP or buy kits and cary them with you. If you are going to mostly use and service them in the US I'm sure you can have a great support from the SB members.
It also makes sense to see what your local team is diving and stick to that, it's not critical but helps in some cases in terms of getting replacement parts etc.