I love the Swift. There isn't a big step up from .22-250 to the Swift but it IS a step up. The only negative I can offer with the Swift is that in some rifles like my old 700 VSSF the Swift works better with the magazine loaded one round short of full, otherwise it'd tangle up / jam up. I didn't experience any measurable difference in barrel/throat life between .22-250 and .220 Swift .. I pushed both very hard. I also didn't notice any difference in case stretching, both are tapered enough they're built to grow.
The negative right now would probably be brass. In the days I shot the Swift (i've owned 4) WW .220 Swift brass was very good, hard as hell, consistent, and accurate. I''m not hearing good things about WW brass now. I would not want softer brass at Swift pressures. Sure as hell not going to load it down. If you want that level of performance it might be worth checking into .22-250AI, .22 Creedmoor, or a .22-243 for the availability of better brass.
Tom
