I've played some bolt on smiths, from the old burners, to the higher end bolt ons of today and they do play great as well! Even a 3 piece maple version still plays great! But the more laminates in the body and neck, the brighter and more responsive the bass gets.
Smith used to offer an elite bolt on model but doesn't publicly offer it anymore but he will build it for you. It costs the same as a similar neck through model since it takes pretty much the same hours to build.
Can't go wrong with any smith model imho... they all have the same great build quality and sound.