I just picked up a Leupold vxII 1-4x shotgun scope to put on my cz550 .416 Rigby. I opted for the shotgun version because of the heavy duplex. The only other difference is that this model is parallax adjusted for 75 yds vs 150 for the rifle version. I had originally planned to just have Leupold reset the adjustment to 150 yds, it's a nominal charge for the service ($10).
My question is, do you really think it is required. Especially considering the ranges I'm likely to use this at.

This also brings up another question:

Are you more likely to encouter parallax induced error shooting a scope set for 150 yds at say 75 yds?

or:

Shooting a scope set for 75 yds at say 150 yds?

I think the difference will be minute, so unless you are planning to shoot meerkats at 300yds., don't worry about it unless you experience a problem while shooting.

George