Semi-finalist NY Golden Gloves in the 16 year old bracket a long long time ago. If you saw my nose you'd have no doubt lol ...

Chuck-375, this is the reason I went to a 2 x 7 Leupold, which has the 33mm lense....more light.

If you are hunting in the spring. You probably will not need a bright scope as there will be snow everywhere. It is a very bright back drop!
You might benefit from it on a Fall hunt.
I would suggest finding a light weight scope as you might have to climb a bit and those big bright scopes come with a price (weight). I personally do not care for a scope over 15 oz on a Alaska type hunt.

Agree. My Rem XCR II in 375 Weatherby weighs 7 3/8 pounds iwth scope unloaded. I'm pretty happy with that weight since it weighs one pound less than our Rem BDL 270 with an old Redfield 3x9 on it, that I've been hunting elk with for a long time.

i think for my 375 its going to be a 1.5x6x42 both zeiss and nikon have them the nikon monarch gold is 1/2 the price of the zeiss but until i decide which one my leupold vari-xii 2x7x33 should be just fine. i also have the leupold 1.5x5x20 but prefer the 2x7 and up for dusk and dawn.

I have 1.75-6X Leupold VXIII on my .338WM. Light gathering ability not a problem. As wi others I set it at low power & then adjust as necessary. Truly appreciated the low power when I dropped the hammer on my Brown Bear @ 30 yds & closing.

As for higher power, such as 8X or higher, I don't think it is needed. Some may disagree. But, on my two BB hunts, both guides did not want you shooting at over 100yds & that was their goal to get you to within at least 100yds.
At long range (over 100yds) risk of wounding was too great- and then you had to go after a PO'd bear, hopefully not into alders.

I have not used a 1.5-5X but would think there would not be any detectable difference with 1.75-6X @ low power range.

I also used the above rig on my Namibia plains game hunt taking kudu @ 100yds, oryx @ 175yds & zebra @ 250yds. Its also my go to elk rifle.

If it were me I would use the 1.5 you already have- unless you just have to have another scope.

I also like what Bear says about backup iron sights. On my 1st .338WM I had them & had them sighted in along wi the scope. Good luck on your decision and the hunt. Nothing like the excitement of spotting a "keeper" bear, stalking it, waiting for the opportune moment
& squeezing the trigger (which is/can be anticlimactic, if EVERYTHING goes right.)