Braveheart lists the regular Grizzlies at 2 3/4" long and 1 1/16" wide and the El Grandes at 3 1/16" long and 1 1/8" wide.
I have the old 190 El Grandes and they actually measure 3 1/8" long and my new 200's are 3 3/16 long by 1 3/16" wide.Those figures above should still be be very close.
The new ones all have the 25 degree grind but you need to be aware that some dealers may still be selling some old stock so I would want to know which I were buying.
I can't imagine any durability issues with any of the grizzlies,at least as far as whitetail hunters are concerned but in either model size,the heavier versions will have the thicker,stronger blades.
I agree with ErikT that you can go as heavy as you want as long as you go up in spine to handle it.You may not,however get the finished arrow weight you wanted.