I have been diving a Scubapro Mk10 with two Scubapro 109's with the white G poppet in them. My 109s are super nice with my main one looking like it was never dove at all. Through this board I was able to purchase a Mk25 at a great price and got it all serviced. The equipment tech is insistent the 109s have to go and that I will get 0 benefit of using a MK25 with them. He has said its time to move to G260's or S600's but I love my all metal 109s. It is really a weak link in my setup if my 109's are using the G series poppet? I do lake diving and am turning my focus more and more to wrecks. I get my 109s off ebay from a guy that cleans them up and rebuilds them and they look new. Is work is amazing. So I like my 109's what am I going to get from moving to G260's or S600's? I do plan to move into twin tank deco diving in the fall and tart the dive season off there next year. I am in the midwest and and focusing on wreck dives. I know there are a lot of Scubapro equipment guys on here so would love to hear the pro's and cons. I picked the 109's so I can have an extra sitting in my save a dive box and fix them myself anywhere in the world.