This seems like it will be the perfect guest room bed!  I can't vouch for it's durability as we just assembled it.  We added L supports under each bed and leg.  We also plan on adding a sheet of plywood under each mattress although the slats seem to be close enough together.  This is just our preference. Also the slats are pieced and have extra screw holes for optional positioning of the support legs.  These two factors will affect the strength of the slats.

Please note...the directions are sketchy so look them over very carefully as you put the bed together.  The directions don't say much...mostly just pictures so make sure you check those pictures out well.  We originally got a couple boards on upside down and had to redo them.

Overall, I think you will be very satisfied with this bed for the price!