Even though I'm not a pear, I have perennial ride-up problems with boyshorts. I have the shimera and find they don't RIDE up so much as ROLL up. But they're not as bad as some. What makes them a problem for me is that even though I have a relatively long rise, they seem to come up quite high on me -- higher than my lower rise pants or even some of my mid-rise pants. And they end up feeling sort of "bulky" for want of a better word. In winter they're not so bad -- but in summer they're really too much.
So I'm giving up on that style for now in favour of some hipsters and no VPL other undies...I like the Jockey no panty line promise ones. NO panty line is a bit of an exaggeration, but they are honestly the best I have found, and lightweight, which I like, especially for travel. (They wash out in the sink like nothing and dry overnight.) The hipsters are actually cut a little bit like a boyshort, at least on me.
But I just ordered the Shimera high legs to try (though they may be too high in the waist, also) and the DKNY Fusion briefs. We shall see.