My proposition is to take ONLY that CZ550 375HH with a good scope, like the Leupold VX6 1-6 or something like that. Load it with 300 grain AFrames. Bring as many rounds as legally allowed in whatever country you're going to and give the leftovers to your PH. Sight it in a couple inches high at 100 and you'll be good out to 260 yards are so - PLENTY of range for 99% of Africa.
The money you'll spend on a double will pay for an entire, nice, safari. Ditto a fully set up (multiple chamberings with nice scopes) Blaser.
As many of you know, I'm a "gun guy". I like really high-quality guns that are far less prone to breakage than many. I'm also OCD when it comes to risks, contingencies, what-ifs, backup plans, redundancy, resiliency, etc. etc. I feel pretty confident in saying that I'm more anal about contingency planning than anyone reading this because its part of my personal and professional life all day every day.
So in light of those facts, let me tell you a tale:
First trip to Africa: Guns and Ammo never made the flight and were lost for 3 days.
Second trip to Africa: One of my rifles was jostled or dropped by the crew and wouldn't hold zero.
Third trip to Africa: Missed a chip shot twice...still never know what happened there as I sold the gun in anger.
Fourth trip to Africa: A mopani twig jammed into the safety and broke it clean off of my mauser making it inoperable. Ammo was lost in J'burg and found SECONDS BEFORE my connecting flight boarded.
Everything that can go wrong WILL GO WRONG in Africa. There aren't enough belts and suspenders in the world to deal with African contingencies.
So when I read "just bring one gun" I cringe, I think that's about the worst advice I've ever heard. Every trip, "just one gun" would have spelled disaster for me. If you like Blasers or double rifles or CZ550s that's just grand, but bring two guns. Bring two different calibers so you have 2x the chance of borrowing ammo in a pinch. Make sure they both will kill 100% of your game on your list should one of the guns be unusable.
As for a double rifle critique, they are worth every penny
if you value your life and you are more proficient with a double rifle than a magazine rifle for instinctive shooting. While you can save $10,000-$40,000 by not having a double rifle, you can't be made no-longer-dead for any amount of money. I believe I have a better chance of saving my own life with a double rifle during a charge than with a magazine rifle during a charge based on experience/muscle memory/less mechanical failure. Not everyone can honestly say that but for me its life insurance. Why? Because I've operated a bolt action rifle for perhaps 5,000-10,000 shots in my lifetime, 95% of that time sitting at a bench where the experience is irrelevant to a free hand shot and reload on a target instantly? On the other hand, I've operated a double trigger side by side barreled weapon perhaps 200,000+ shots in my lifetime? Go with what you know as your life is ultimately in your hands, not the PHs. (his attempts to save your life are "good faith effort" only)