OK
I'm out of IMR 4350. Got to get a new batch.
going for the 8 lb canister this time.
Should I switch to H 4350?
For
30-06 with 165 grain
270 win with 130 grain
7X57 140 to 160 grain

H-4831 for the 30-06 and 270, H-4895 for the 7x57.

Are you unhappy with IMR powder? When you switch you have to redevelop the loads all over again not to mention that your rifles may not shoot well with Hodgdon powder.

Danny Boy

If you're like me (cheap) you might consider Accurate 4350. It can be had for $20 less here It is very close to IMR-4350 in burning rate and performance. If you are insistent on IMR-4350, they offer it also for $109.95 (exactly $20 more than the Accurate version for an 8 lb. keg)
Another option to consider for those calibers would be Reloder 19 or maybe Vihtavuori N-160, but if you are happy with 4350, I don't think you would notice that much difference between the Accurate and IMR versions.

Why switch? If you are happy with IMR 4350 you will probably spend less time working up loads with the new lot. You have existing data for your rifles right? Just remember to store it properly. It will take along time to shoot up 8 lbs.

I like the H4350. Using Nosler 150gr boats with 56.0gr of powder I get 1/2" 5 shot groups. But thats with my rifle. Take a few off before shooting it with your own.

Trigger,

My favorite powders for the calibers you are asking about are;
'06 - Reloader 19
270 - Reloader 22
7x57 - H414

Though as stated earlier, Reloader 19 would work OK for them all.

BigBullet

If the guy hasn't found his new powder in the past year, he ain't gonna find it...