a 1.5 hp router is pretty marginal for raising panels even if you can find someone who supplies .25 inch raised panel bits. Your best option if this router is the best you can afford, is to remove most of the material with a table saw before attempting to rout the panels. It's actually possible to do a shaker style bevelled panel with a tablesaw ONLY. Takes a jig to support the panel at a right angle to the table surface, but that's much less of a problem than trying to make a laminate trimmer class router raise a panel.
Seriously. Raising panels is shaper class work. I've done it in sugar maple with a 2.25 hp router in a router table and it was a bear. Took about 5 passes on each bevel to get the job done without tearing out something fierce.
You CANNOT raise a panel with a handheld router, you WILL hurt yourself and ruin your workpiece. An additional problem is the likelihood that your router simply won't be able to turn a big panel raising bit and will tear itself to pieces trying. For lower horsepower routers they generally recommend vertical bits that require the router either to be mounted horizontally or require a very tall fence so the panel can be run through the table on edge.
Certain types of router bits shouldn't be cheaped out on, and Harbor Freight bits are cheap. Panel raisers are under such high stress that the braising has been known to give out on the carbides on cheaper ones, and the cheaper carbides have also been known to crack and fragment if they strike harder wood.
Be careful and take some time to really study what you are intending to do before you do it. It could save you a lot of pain, suffering and wasted materials.
Don't get me wrong, Ryobi makes a decent tool, but with a 1/4 inch capacity it is clearly made for the light duty market.
Check out Eagle America router bits
eagleamerica.com/Default.asp?bhcd2=1139622255