Other threads cover the topic of DIN vs. triclamp. I've used both and prefer triclamp. DIN and SMS are nearly the same. Threads on either are NOT the same thing you normally worry about in a brewery. They are external to the joint, rounded, broad clearances, and easy to keep sanitary. They are made to be clean and sanitary. The only real difference between DIN and SMS is that DIN has a tapered plug and SMS is a flat face. DIN is metric tubing, SMS is in inches. One of my big complaints with either is that the gasket stays in the fitting and is not removed for sanitation like triclamps are. Other big complaint is male/female issues with hoses and any other connections I need to make. Try to join two hoses. Need special adapters. And carpal tunnel? I have much higher incidence of wrist fatigue with screwed joints than with triclamp. And hoses & fittings are heavier with DIN/SMS. And I don't like to be required to use tools to do my job. Big, heavy DIN wrench never where you want it. I shouldn't have to use special tools to do my job as a brewer. So anyway for the difference in price, I'd go with SMS.
Phillip Kelm--Palau Brewing Company Manager--
Worldwide Brewery Installations