Better Late than Never
I realize that by now you've very likely already picked one or the other .22 Magnums (Remington or Ruger), however, I just signed up to Rimfirecentral and I happen to own both the Remington and the Ruger .22 Magnums, plus a Magnum Research .22 Magnum. Obviously, .22 Magnum used to be my favorite round.
To make a long, virtually endless discussion short, I'll attempt to summarize the primary advantages of each rifle. The Remington is by far the most reliable. Mine has never missed a single beat for the past 10-plus years I've owned it. Unfortunately, the Remington has few after-market components, with the most important of which being the availability of ANY after-market high-capacity magazines (at least that I'm aware of). Consequently, shooting it with the anemic 9-round magazine gets boring real fast.
As you very likely know already, the Ruger has by far the most after-market components available for it, including two brands of after-market, high-capacity magazines. Unfortunately however, of the three rifles, the Ruger is by far the most temperamental, especially when using any of the higher-capacity magazines. It can also be temperamental when using the factory 9-round magazines on occasion (dependent on what ammo you're using). In my opinion, the best attribute of the Ruger is that it has the adjustability to become a virtually non-stop rifle build project. Wherein there are numerous after-market parts available for just about every single part of the gun.
In my opinion, the Magnum Research (at least the version I own, Model MLR-1722M Magnum Lite) is hands down the best of all worlds when comparing .22 Magnum rifles. It too has the same high-capacity magazine issues that the Ruger has, yet the remaining build quality of the rifle far exceeds that of the factory stock Ruger and/or the Remington.
With that being said, the most important attribute of any firearm should most likely be how it fits and feels to whoever happens to own it. There again, the Magnum Research (with the thumbhole Boyd's laminate stock) fits and feels the best to me. However, I'm pretty certain that you can purchase the exact same, or very similar stock from Boyd's for either of the other two .22 Magnums.
By the way, I previously mentioned that .22 Magnum used to be by far my favorite round. That all changed drastically the day I purchased an Armscor/Rock Island Armory .22 TCM 1911 clone. I haven't taken any of my .22 Magnums out to the range since I shot my new .22 TCM. I highly recommend it to anyone who likes extremely fast (2100 fps), extremely accurate, flame-throwing bullets that have virtually zero kick whatsoever. That, and the 19-round capacity of the factory stock pistol make the .22 TCM almost incomparable with any other .22 caliber firearm being offered on the market today. I highly recommend it for anyone who currently likes the ballistic characteristics of .22 Magnums.: Blasting_