strollers for toddlers -- how long can a toddler fit in a Bob?

I've always wanted to get a Bob -- lately it's become apparent that our LO is getting too tall for our VERY expensive travel system. I began to look at online comments re Bobs and a lot of people say their toddlers outgrew sooner than expected -- none say how old a toddler or how big. Looked all over the Bobgear website to try and see how old or (better yet) how tall a toddler a Bob can accommodate. They tell you how old a child should be to use a Bob, but not how old or big is too old/big.

I'd hate to get the thing then have to get rid of it in less than a year. Anyone have an older toddler in a Bob? My LO is about 21 m and a little over 34" tall.