Fenn XT Double with new paddlers?

Hey Guys,
I am considering a double ski to introduce new people to the sport once Covid restrictions pass. 

I am wondering about the stability of the Fenn XT Double (in Glass if it matters). I know a lot depends on the natural balance of the newbie, but in general, assuming the newbie is  not a total oaf, do you think the XT Double's 20" beam is stable enough to take a newbie into small ocean conditions (as in less than 10kt wind and very small or long period swell)? I thought 19" was immediately stable in all but extreme conditions right from the start, but I hear others comment about the instability of boats like a V8pro too. 

I can also get a Nelo 600 which at 24" wide and obviously more stable and easier to store, but I feel like on flat-ish water the 600 would feel slow, while the XT-D still has good speed potential if I put another experienced paddler in it for a bigger downwind. 

So what do you think about 1 "never paddled a ski" novice in the XT vs 600? and also the overall enjoyment with 2 advanced paddlers? 

Both doubles will be fine. I take beginners out in a v10 double with no issues, which is tippier than an XT or a Nelo double. About the only double I wouldn't take a beginner out in is the top end carbonology one.

The weight and height of the beginner in back relative to the pilot makes a huge difference. I have a v10 double. Put a 5 foot tall 100 pound woman in the back and i dont care if she is break dancing back there, i will barely feel it. On the other hand put a tall unskilled guy in the back who is heavier than me and it is a nightmare even on flat water. 

I think it depends a lot on your experience paddling doubles too. I have very little experience in this area. I am as happy as a pig in mud while paddling an XT single or equivalent in a messy, cold 30 knot downwinder. However I'm pretty tense in anything other than calm water in my XT double with my partner who does not otherwise paddle. My partner is as relaxed as can be though because she has no idea how much I'm struggling. We've never fallen out so I think the ski is more stable than I give it credit for.
A mate of mine has a Nelo 600. He and I have taken that out a few times in various conditions and I am much more relaxed in that ski. No doubt it is partly due to paddling with another experienced paddler who just happens to have vast doubles experience too. The Nelo doesn't feel terribly slow but it's hard to see it being as fast as a ski so much longer and narrower.

Has anyone tried the 600 with only one paddler? How does it perform? Given that it’s still shorter than a lot of singles I thought it might be similar to an entry-level single?