[spaghetti]

The significant difference between the two suits is in the inside: the Master Pro is open cell neoprene, while the New Titanium is coated inside with a film of titanium paint. Both solutions are good for thermic insulation, but personally I prefer open cell: you have to lube it when you wear it, but then it's warmer, softer and more comfortable.
So at the end between the two I'd pick the Master Pro, which is also better sealed and stiitched.
About Omer in general, they make some of the world's most popular and innovative products for speafishing and freediving, with a good quality/cost ratio.