We have a 303RLS. We have to park on the street to pack and unpack, so access with slides in was very important to us.
With the slides in, you can access: refrigerator and freezer, upper right hutch cabinet, lower right hutch cabinet (perfect size for canned goods), right hutch drawer, linen closet in bathroom, left door into larger (middle) closet, door into right closet (only partially if you add the height of both a residential mattress and 4" foam topper), both nightstands, cabinets above bed, all of the bathroom.
Our first trip we had lots of stuff to load so we put the curb side slide out about halfway and put stuff in the middle of the living room. If you are nimble, you can climb over the dinette/chairs and get there with slides in.
With a little preplanning (like bread in the upper right hutch cabinet and knife/plastic silver in the right drawer), you can stop for lunch.
We just completed a 5 week trip, and had no problem finding accessible places to put everything to unload without opening slides. Of course at the end of the trip there usually isn't as much beer to unload

In our previous trailer (just one slide, rear door) we could access everything except our pantry, so I am used to packing food in a couple of boxes. It keeps you from taking too much food (sometimes), and actually was easier in the Reflection. Making the bed (or unmaking the bed) is impossible with slides in.
We looked for close to a year to find something in our length, weight and access requirements. Like cgoodnight said, with 2 slides it is nearly impossible to get to the main living area. We do really like the extra room when set up.