V10 Sport vs Swordfish S

I have been paddling a V8 for the past two years and think its time for an upgrade.
Mostly do river paddling, but on the occasion try to catch a wave or two on a passing by boat.
Currently leaning towards the SFS. Looking at either the glass or performance layups respectively.

Is there much of a difference between the V10S and Swordfish S in terms of speed and stability?

Best thing is to paddle both.

As I have been looking for my intermediate boat I have realised that the specs and what other people say are almost meaningless.

Your weight, your ability, the way you paddle and where you paddle will have a huge difference on how a hull performs for you. I have been in boats that are supposed to be stable and I struggled immensely and then unstable hulls were easier.

If you can paddle both hulls in your conditions, you will have your answer. 

M

The G3 V10 is more comparable to the Swordfish S as it has much more Rocker like the Swordie. 

The G3 V10 is more comparable to the Swordfish S as it has much more Rocker like the Swordie. 

Agreed that paddling both will probably tell you which boat is better for you. I have the SFS. I have not paddled the V10S, but had a stellar SR and Fenn XT of the same beam. 

The SFS bucket is tight but not uncomfortable on me, and I have a 33-34" waist. If you are larger around the mid section, epic's are known to have larger buckets.

Another thing to consider is the 2 boats have completely different hull profiles. The SFS has a decent amount of rocker as mentioned. The V10S is basically flat keel'd. For flat water like you paddle, less rocker may be good since rocker is mainly to improve handling in waves.

I'm not sure if there would be any perceptible speed difference between the 2.  Probably quite negligible until your skills and aerobic training are advanced. Though in a sprint, skinnier boats can achieve a noticably higher speed before hitting the hull-speed resistance wall.  

Going from 52 to 48 or 45cm beam will be quite a difference stability wise. In a V8 you can drink a beer and pay no attention to stability and be fine all day. In the SFS, I can relax and do not have to have laser like focus by any means. It still has great stability for its speed, but it will be significantly less stable than a V8. I still go for an occasional swim when im not paying attention, but I am also in the ocean. Assuming you have good form already developed you can probably adapt to either. In flat water all but the elite boats should be approachable to someone with some determination and average ability. 

Best advice is to try both if you can. 

Finally one i can answer as I actively paddle both.  SFS is much twitchier than sport.  But once you get used to any new boat, they all become "stable" to you.  I almost fell in 10 times on a lake w/ my SFS's first paddle, but now it feels stable.  Much narrower bucket and higher gunwales on SFS.  I wear size 38" waist pants, 200 lbs/90kg, and SFS is fine for me, just noticeably more snug.  The higher sides make me swamp much less on downwinds (perfect boat for me for Gorge for that one reason vs v8pro and bluefin).  But, SFS is tougher to remount due to these high sides.  V10Sport is much more stable while moving slowly or stopped, but once under way, most skis are fairly stable, imo, unless rough side chop.  i did a speed test one day in my black tip V12 g1, red tip v10sport, and glass SFS on flat water.  V12 was fastest, and while the SFS felt faster, the times were inconclusive--some roundtrips faster on sport, then sometimes faster on SFS.  I think SFS is a downwind boat.  Sure you can use it in other applications, but i think Sport is more of an all-around boat, better when you really do not want to fall in (winter time/cold, unfamiliar waters, choppy confused waters) or just want have a relaxing paddle, just as good in flat water, usable by guests moreso than SFS.  Both are excellent boats.  I love them both.  You cannot go wrong with either.

If you are just paddling rivers and flatwater try using a smaller rudder with either boat. I have a chopped down rudder for rivers which is smaller than stock. Not only does it reduce risk of impact with underwater objects but it also affects stability and responsiveness. Going from a surf rudder which keeps you locked in, a stumpy rudder lets the boat roll more which means that my fear of not being able to turn in a narrow river unfounded. The boat can be "edged" more easily into the turn, the rear is not as locked in so slides around a turn a little.  It makes the boat feel as though it suddenly has more rocker in comparison. Totally changes the feel and far more fun

Of course smaller rudder means less drag which is another bonus.

I reckon any half competent paddler will eventually learn to handle the stability of any immediate ski on flatwater. Falling in on a river is even less of a drama on a ski than open water. So it may just come down to which feels the most ergonomically laid out for you, which can only by found by testing on water.