A higher efficacy bulb like the Xtra-Vision, Xtreme-visions etc are still within OEM specs...the filament is just more precise, better wound and placed...to allow a better more precise beam than a stock bulb. Even though the bulb is still 1000 lumens, they can actually put 80% more light in a specific spot on the road ahead provided the optics of the enclosure are designed well enough to hopefully take advantage by producing an intended beam pattern. In a 1990-2005-ish GM enclosure, I have my doubts.
The glare cap issue aside, some optics simply can't handle the extra whatever% lumens of the HIR bulb. So the conversion is not universally applicable. There is a point at which the light becomes intense enough that there are internal reflections made manifest only by the increased intensity. The reflections always were there but at lower outputs the effects were less evident perhaps not noticeable.
As the light increased light of the HIR bulb bounces around these poorly designed enclosures it spills into areas of the lamp that were never intended to focus a beam pattern. Some side effects of these internal are unwanted external reflection outside the headlamp. As good as the headlamp is on my 2009 Corolla, even with a proper modern glare shield, I tried the 9012 bulb. In clear weather things were just fine..lots more output etc, yes..good. However any weather, mist, snow, rain, even slight fog and there was a optical aberration about 3-5 feet up off the hood in the light pattern that was very distracting, making it harder to see in these conditions compared to the normal 9006 bulb.
At night the low beams are the constant especially in any kind of weather, so despite the increased output this issue was enough to make me put the 9006 bulbs back in and the problem was gone.
I too drive 98%+ rural, so I can relate....the 9005->9011 high beam was a monumental upgrade. So much reach, no critter has gone unnoticed. When I flip them on with passengers, even if they have seen them before the reaction is always the same....
"WOW...your lights sure are bright...I can see everything."
My advice, get a minor upgrade like the Xtravisions for the low beam 9006 and put the $$ where it will do most good for your driving environment & go 9011 HIR for the high beams. It is the formula I have used in the Corolla and am expanding to the other GMs in my stable.