Here are some samples showing how wide conversion lenses can help you get more into your interior shots.  The first image shows the A80/95 at its widest zoom setting - no conversion lens. Other than color correction, these samples are untouched.  

---

Some tips for shooting interiors

Use a tripod whenever possible.  Most interiors aren't bright enough for handheld photography and the built-in flash is inadequate.  Besides allowing longer exposures than you could handhold, this also allows you place the camera in the corner of a room - just flip the LCD around so you can compose, use the self timer, and get out of the way.  

Level the camera so it's not pointed up or down to avoid converging veritcal lines.  

If there are windows or glass doors in the shot, try to shoot at a time of day when light levels inside and outside are close.

Or, (with a tripod), take correctly exposed frames of the interior, then take correctly exposed frames of the exterior, and combine these in Photoshop.  If the interior is lit with incandescent light, you may want to change the the white balance to the appropriate setting for the exterior exposures.  

Click on any thumb to see full size image.