I don't have Lightroom, Jeff. What is the difference in the print modules?
I always prefer printing from Lightroom vs Photoshop for a variety of reasons–first off, Lightroom only cares about pixel dimensions, not size and resolution. So, if you need a small print, simply set the dimensions of the cell size and the resolution auto-flows...big print where you need less? again, it auto-flows. So you don't need to spawn off multiple files just to print different sizes.
Lightroom has an optimized upsampling that is image adaptive. If you upsample, LR interpolates between Bicubic and Bicubic Smoother depending on the size.
The last phase is output sharpening...which I had an involvement in since Adobe worked with PixelGenius to bring output sharpening to Lightroom.
The printing workflows is, in my opinion (which of course, I'm biased about) superior to Photoshop.