Re: make my decision for me
The RUM will suffice. The Lapua will outperform you expectations. You can get the Lapua to shoot as flat if not flatter than the RUM with 225-250 grain bullets, many of wich still have good b.c's. I really like the 300 RUM, but when you go bigger it just gets better.
Then the actuall rifle comparison. You cant even compare the quality of a Senduro to an Accumark. Wby wins hands down. The action is stronger, smoother, and has a shorter throw. The Accumark is about ideal for a hunting rifle when it comes to weight, not to heavy and not to light. That being said, the Wby is also alot more $$$ and they have almost 0 aftermarket parts.
The Remington is good, actually the Senduro's are great, especially for the price.