I've owned all 3. The only one I still own is the 6.5x55. The effectiveness of that long skinny bullet is amazing. Plus you can get heavier bullets if you want. The heaviest I've seen for .243 was 105 gr and the heaviest I've seen for .270 is 150 gr. The Swede has bullets up to 160 Gr. Plus they have a higher sectional density which helps give deep, straight line penetration on game. The Swede is still common in Scandinavia for moose.