Hi Matty, I am 46yrs, 95 kgs and been surfing for 30years and came down from longboards after shoulder reonstructions and have both a 6'10 Advance and a 6'5 Elf. It is a big step down from the Addvance 56 litres to the largest ELF (6'5) at 44 litres. Here are my thoughts;

The Elf is an easy board to catch waves for it's size, but is is nowhere near as easy as the Addvance.
The Elf has a flat rocker and steeper take offs are tricky, the Addvance is the most forgiving board at take off I have ever surfed.
The ELF will have about three more gears over the Addvance - It just goes like the proverbial.
The ELF will definately give you more performance than the Addvance.
In overhead waves, unless they were forgiving takeoffs or you are very competant, I would be looking for something with a little more rocker.
If you really want to go vertical, I think you need a bit more rocker as the ELF turns need to be drawn out a little more than say a similar size Spitfire, however you will still turn the ELF more agressively than the Addvance due to the shorter length and lower volume.

In summary, as you are on an Addvance, it sounds like you are not an advanced surfer so I'm not sure the ELF would be the right board, but it would still be alot of fun trying. Others might disagree as a lot of folks really love the ELF so wait for their comments as well before listening to this busted old kook. If you can pick up a 2nd hand one and keep the Addvance would be a good bet.

Have fun.

PS Hint to Chris - I think the FW range has a real gap in it between the Addvance and all the other Hybrid boards that "need" to be ridden closer to the "optimal" volume and have a much flatter rocker. I love my FW's and have a Pnator and Addvance for conditions that suit, but for overhead nice waves, I still have a PU board that I prefer. I'd like to maintain a bit of volume and rocker, without going as wide as the Addvance.

I'm right about your same size and love my 6'3". It will definitely feel smaller, but it will still offer plenty of float for you. All of the comments about the lack of rocker in the nose are right on the money, which makes takeoffs a bit tricky at times, but once you get it the board is amazing. Caught one yesterday that was steep for where I surf, head high and super fast - the Elf took off and went straight down the line at amazing speed. Threw in a full cutback once the wave slowed a bit before kicking out the back. So impressed with this board!

Once the waves get to the head high range I wonder if a Spitfire or a Jacknife might not be the call, but for anything less, the Elf is the board of choice.

Good point STC67

Thanks heaps guys really appreciate the feedback, I was wondering about the 6'3" so I will go and check it out and see if they have one I can borrow for a tryout. I get the point about the rocker as in Perth we have a lot of dumpy beach breaks which is a concern. I have a 7s but I love the firewires and want something different for my quiver that is more responsive. While age is still just on my side I want to throw it around a bit while I can.

I think the idea is good. The 7s has a very flat rocker as well. How long is it? Maybe try a larger Hellfire

For dumpy beachies, I'm not sure the El Fuego is the call. Great for point breaks or slower waves though. STCs suggestion of a Hellfire is not bad.

Yeah for steeper waves the Hellfire will be my call.
Today I had tons of fun on my pnator on some chest high waves in maine. Very playfull board

yeah depends on the size of the dumpy beach break. I have had a blast on hollow beach breaks on my El Fuego in head high surf, but yeah, you do have to pay attention to the rocker whereas the hellfire you might be able to push it on the drop a little more, move forward on your board in the tube, etc.

Cheers