I was just recently in a similar dilemma... I was looking to fill a hole in my Stainless M77 MKII line-up between .22/250 and 7mm Rem Mag. I was hoping for a .260 Rem, but when a .270 MKII stainless became available, I jumped on it. Subsequent to purchasing the .270, a grossly overpriced M77 MKII Stainless .280 was located in New condition.... I really like 7mm bore cartridges, but would have had to source brass and dies also... I went back to my reloading notes on .270 and .280 and concluded I would just be throwing away several hundred dollars to make that switch... the .270 stayed.
Having said this, given your circumstances, with brass in hand and both barrels, there is no doubt that I would have made the same decision as you did.
I totally agree. The 270 would have been the far better choice for me from a practical standpoint for me as well. I had the dies, brass and bullets on hand. I did have to scrounge up the 280 brass after the purchase, but do live close to the border of Maine and have a postbox there so that makes US purchases possible for loading items. Still need to find some dies.
I think that most chose the 280 in this thread cuz the gun-nutter in us like something a bit different. My reason was the same and it will fit in well with my 223, 257R and 35W given the Remington theme.




















































