I'd say if I had steady access to Boli RC with 3-5 years on em' I'd stick with them.
At first, I wanted to say the Liga Privada No. 9, because it's my favorite. But here's the thing, it's not a cigar you can smoke every single day. Some days you might not want that much power. I think these guys got it right. The Boli RC offers enough flavor to satisfy completely, but doesn't knock you down. It's not a powerhouse. It's complex enough to keep you interested, and calm enough to be smoked at any time of the day and for any occasion.
I'd have to say, yeah, if you only get to smoke one for the rest of your life. Boli RC ain't a bad choice. I might go with a Monte #2, if I could guarantee quality, or a Cohiba Robusto, but it would be one of those three, and I guess it wouldn't matter which one to me.