The only reason for 2 more inches of barrel is more velocity.
I think it best to get in in 28" then shorten if appropriate.
This is base on experience with several rebarrels on several different rifles.
Original barrel 24" Douglas Premium- 270 Win cartridge. 140gr bullet accuracy load 3190 FPS. 0.75 MOA consistency.
Replaced barrel, 27" Lilja- 270 Win cartridge. 140 gr bullet accuracy load 3200 FPS. 0.25 MOA consistency. Same powder and charge weight in both barrels.
Original barrel 30" Lilja 8 twist 3 groove - 270 Allen Mag cartridge. 169.5 gr bullet accuracy load 3400 FPS. 0.25 MOA consistency
Replaced barrel, 28" Lilja 8 twist 3 groove- same cartridge. Same bullet. Same velocity. 2 0.25 MOA consistency. grains less of the same powder.
The 28" barrel on the Allen Mag is smaller contour and way way more convenient than the 2" longer barrel.
Knowing what I now know I'd go with the shorter barrel as velocity loss due to taking 2" off of a longer barrel will not be noticed at all by whatever it is that you're shooting at.