Unless you just cannot live without the standard 250, I`d go with the AI.
But, i`ve seen nothing modern in that chambering that compairs to the handeling of a Mod. 20. And they can be found at moderate prices. If you can, get one with the peep on the striker, will get you out to 200-250 yrds, took one like this P-doggen one year to Wy. I had two...my son killed his first two bucks with one...he now owns it.
Modern action, SA 700 chambered for the AI. Much better cartridge than the parent. Mine is on the SA700,24 inch Douglas barrel, you can get one perfit, chambering etc. for about $325 from Douglas.. Go ten twist...you can push the heaver bullets, 115-117-120, close to 2900fps. Lighter bullets go much faster. Look up the balistics. I absolutly love mine, and wouldn`t be without it. Also. spend a few more bucks on a H.&S stock.You will not regret that. I would quess you would be looking at13-1,400 dollars.
Good luck.