We had a Casita
FD for 8 years. Loved that little guy. Now have the 21 and wouldn't go back. We looked at the 19 but it just wasn't enough 'more' than the Casita
to write that check. Still had a crawl over bed and a smaller bathroom. Plus we were not comfortable in the dinette with the high windows
. Then along came Reace and Tammy with the 21. I though I wouldn't like the front bed but it's a non-issue. It's tucked up front beside the huge bathroom. No more crawling over each other in the middle of the night. It feels very spacious inside. We can walk by each other in the aisle and the rear dinette is huge. So nice to lounge around back there and look out, eat, play cards with friends, watch a movie, you get the picture. Tons of storage. Easy to tow - who knew the tandem would be easier to tow?
That being said, it depends on how you are going to use it and what you are comfortable in. If our son decided to get a new trailer (they have a 10 and 11 yo) I would suggest the 19 with the cot option. Go to a rally
and look at the different models but we are still loving the 21!