There is access but not much room. If you're a very large fellow you might have a hard time but your average Joe won't have any problem. My wife would've vetoed the purchase if she couldnt use the bathroom and bed while underway. Put a little bumper pad on the trim above the bunks to keep the door from nicking it because it does contact it when opening with the slides closed.
Here are pictures of a 350TS which is almost identical to a 357QS except for the small kitchen slide and queen vs king bed.
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Ron Hanson
2009 Georgetown 350TS (bunks)
400W solar, 440AH 6V GC2
2009 Ford Edge AWD Ltd towed
2011 Honda Fit Sport towed