For large-ish chests, I'd suggest looking at both the Leigh D4R and the Porter Cable OmniJig. Both allow you to adjust the spacing to come closer to the look of hand-cut dovetails. And, both allow stock up to 24" wide. The OmniJig is larger and heavier, but includes a number of bit-depth guides that can be handy for "saving" the setup for different stock thicknesses. If you have the space for a "permanent" DT station, the added size and weight wouldn't be an issue. But, it might be an issue if you need to move it around.