But the battle to displace the likes of international regulars, full-back Rob Kearney and flankers Peter O'Mahony and Sean O'Brien, has the young pair trying to make themselves more versatile.
"I can play both (at 6 and as a second row)," said Henderson whose form with Ulster saw him get earn his first Ireland cap against South Africa last November.
"I'm swapping in and out of both, but I'm young at the minute, so it's a matter of getting game-time. I'm happy to play either when I'm selected for either positions, even for Ulster.
"Everyone is concentrating on getting selected for the first few Rabos (RaboDirect PRO12 rounds), then the Heineken (Cup) and then selection comes for the (Irish) camp after. I'm keeping my options open."
It was a sentiment shared by Athlone ace Henshaw who has made the switch from full-back to outside centre and is learning from the best in the business.
"Versatility is probably key in being a back. I like playing two positions, so I'm really going to stick to one," admitted the reigning Connacht Player of the Year and IRUPA Nevin Spence Young Player of the Year.
"Further down the line, I think I'll have to settle into one. I wasn't too concerned about the move to 13 because I played a lot there underage in school so it's obviously a way higher standard now, but I try to look at tapes of what Brian O'Driscoll does and a few 13s around the world, just stay focused and keep to the task."
The latest Ireland training camp, which took place at Carton House earlier this week, gave Henshaw the chance to mix it with O'Driscoll, who scored his famous hat-trick of tries against France when Henshaw was just six years of age.
But he is not about to be overawed by training alongside one of his heroes, adding: "I've been swapping in and out with Brian, getting to know the roles of playing 13, picking up some basic tips about the position and he has been really helpful for me and has given me some invaluable tips.
"It's a tough challenge to go out with people you looked up to, your heroes that you watched since you were a young kid.
"I tried to keep focused, keep my head down and try to play my normal game and get on with the task. That's all I can do and keep positive about it."
For the 21-year-old Henderson, Ulster's Younger Player of the Year last season, it is about learning from the professionalism of the senior players and hoping it rubs off on his own game.
"Growing up these (guys) were my role models, but more in camp, you learn habits off them. Maybe it's not just on the pitch habits, maybe it's off the pitch habits, doing your extra bits and pieces with your diet, all sorts of lifestyle things.
"Just learning off them, people who have been professionals for longer periods of time...picking up better habits off them which is good."
The two youngsters were part of the squad that travelled on Ireland's North America tour in the summer, with Henshaw making his debut against the USA and Henderson taking his caps tally to six (including a first start against the Americans.
They are both looking forward to the challenge of working under Schmidt, with Henshaw stating: "I really enjoyed it (the summer tour). Really delighted to get my first cap over there and I'm just really keen to keep going and have a good season again hopefully.
"I'm really impressed with the whole (Irish) set-up. Everything has been really energetic and positive. I have got on well with the lads and I've learnt a lot already. Just really excited about this year and I'm really happy to be here."
Henderson continued: "Joe has been working in the Rabo for a good few years now, and I think he knows a lot of players inside out. His attention to detail is massive.
"I'm sure he has got a fair idea about a lot of the players who will be in the Irish set-up for the GUINNESS Series in November. I think he has a fair idea about what level the players are at."