Brad-

If you hold the paper next to your monitor, does the Lasal Luster paper brightness equal the brightness of a white document on your screen? This is to make sure that the brightness of the display equals the brightness of the paper. If they are not the same, the print may definitely look too dark. Another test is to use an industry standard evaluation image that is not your own, as an evaluation image wasn't created or modified on your system. Here is a great one worth printing:

http://www.on-sight.com/downloads/

Use the Onsight Color Evaluation Image

Wich printer are you using? I can go look to make sure that our profile is up to par as another check.