I saw an R-25 listed in the DHC classifieds. I dont know anything about it. I didnt click on it. Personally I have had my eye on an R-15 chambered in .204 Ruger for coyotes and woodchucks. I do agree with you though that anything smaller than about a .243 is too small for deer. Here in So. MI were not aloud to hunt deer with a rifle other than a muzzleloader, which is what I used to use up untill last season I bought an H&R ultra slug single shot 3.5" 20 ga. I find it hard to understand why someone would need a semi-auto to hunt deer with. I guess if you had a pocket full of tags and a whole herd of em were standing in front of you. Then I could see some lead flying. Anyway I never heard that either model Remingtons were made by Bushmaster I only heard DPMS. I guess maybe the early models could have been. However, I have only known of their existance for a few weeks and nothing that I have read about them said anything about Bushmaster, but what do I know. I didnt even know they made that many calibers for them. I thought the R-15 was .204 and the R-25 was .243, thats it. I guess I learn something everday. Either way because of what I do with a rifle here in MI (strictly varmints) I would go with a .204 or .223 but I was to also use it for deer then I would go for the .243. IMO the 7mm-08 or the .308 is more of an elk or caribou round than a whitetail round. A .243 shouldnt have any problem knocking down a whitetail especially with the heavier 85-95 grain loads. Its all what your going to do with it. For varmints stick with the .204 or .223, for varmints and/or deer Id go with the .243, Then for strictly big game like deer, elk, caribou, hogs, etc. a 7mm-08 or .308 might suit your needs better.
treat every situation like a dog. If you cant eat it or hump it just piss on it and walk away