Is that the new "Pure" Tungsten guide rod that weighs 3.7 oz? I have been looking at trying either that or a Jentra this offseason. If it is the Pure Tungsten, do you use the Glock Store springs? Do you know if Wolff springs will work as well? I haven't run into anyone who's actually tried this new guide rod from them yet.
On topic, I do find that I have slightly more recoil control with my gen4 34 than my gen5, but I find my reloads are much more consistent with the gen5 due to the magwell. That's the single biggest factor for continuing to use the gen5 in my opinion.