Hey Warren... I can tell ya what I know...
I have no first hand experience with the Rockler DTJ. But,, it does review fairly well in most circles with the pro's easily out numbering the con's...and if I recall correctly, the jig has reviewed fairly well in some of the major woodworking mags. Out of the box, the jig is capable of cutting through and half-blind dovetails with several additional templates available for an additional cost. Dust collection is a very nice option available for the jig.. something to my knowledge, the PC's do not have...
I do have a PC 4216 and love it... Solid, well built construction...a very mild learning curve required (for both for that matter) with paying attention to stock width and position in the jigs being most critical for good results. The 4210 comes with a single template used for half-blind, rabbeted half-blind and sliding dovetails.. the 4212 comes with the the aforementioned template plus a template for through dovetails and box joints. Then the 4216 (which can be had for under 200 if you shop around come with both of the previous templates plus a miniature dovetail/box-joint template.. When you start pricing out the templates I think the PC is the better value. IMHO.
Now, if you're looking to make alot of small boxes and not so much drawers for dressers and the like,, you might look at some the router tabletop jigs..
"..... limited only by imagination"
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Skipper the Penguin