Firstly, I want to say how fortunate you are to be in such a predicament. As much I like the 5170P, you are comparing a chronograph with a perpetual calendar chronograph so it is almost an unfair fight. It is probably best to base your decision on practicality - the 5170P is unlikely to have a long production run and if you can get your hands on one, you should not miss out on it. If the lugs did not stick out on my wrist, I would have ordered one too! As you correctly stated there will always be a 5970G in the market. And I am assuming that you prefer the 5970 to the current 5270 which is a very attractive watch too?!