Reading a lot about this but still don't understand how it relates to conditions and individual sailors weight.
I have read that a flexy top is good for high wind conditions because it allows the top to react to gusts and twist off, does that mean a stiff top is better for low wind conditions?
As I'm considering new (and used) gear I have to make sure all the gear is compatible with each other and myself and conditions.
Lots of chat about this on the forums but it's all so esoteric, vague and confusing.
Not really as the sail is designed for the mast the manufacturer uses. So (in very general terms) a Neil Pryde sail on their flex top mast will not twist off any more than a similar model Maui Sails on their quite stiff top mast.
However is you stick that Maui Sails onto the flex top Neil Pryde mast it will twist off more and likely it will be horrible.
You are right that flexier top can be nice in stronger winds..... but only when using the same and compatible stuff. For example my 5.2 has a 428 luff and is supposed to be rigged on a 400. It feels best on the 400 but if the wind is very constant and a tiny bit lighter it feels better on a 430 - but it is the same model mast.
Try to use the mast the manufacturer recommends unless your sails are the middle of the road as far as bend curve goes. Big benefits to having all your sails the same brand, using a brand with a middle of the road kinda bend curve, and then you have a variety of masts that will work.
Or, buying a middle of the road kinda mast and then you have a choice of sail brands that will work on it.
If unsure, tell us what you hav enow and what you are looking at buying. Somebody out there will have tried it already 
OK so stay away from the extremes, makes sense.
The situation is the shop I am buying the GO 155L from shares the building with HotSails Maui who have some gear for sale and it could be bundled together with the board on the barge to save serious shipping costs.
Specifically they have a 2008 HotSails GPS 8.0M sail brand new for $150.
Also a used HotSails 460 RDM mast.
The sail has a Luff of 496 so I can buy a HotSails 490 bottom or top making a 475 mast, then 21CM extension and I'm in business.
But now I'm committed to HotSails masts and RDM and have to figure what all that entails.
Apparently HotSails if a bit flexy top at least according to that 2008 chart.
If you are learning, stay away from a cammed sail like the hotsails GPS. I'd ask some hard questions of the people who are trying to sell a learner that type of sail.
I cannot find any other large used sails on the Islands and this sail is new and only $150 with near free shipping.
Sure a nice new no cam sail might be more user friendly but I can't justify $600 right now.
I seem to be getting along OK on my cammed sail currently.
Getting back to the original question, do I want to go down this road with HotSails RDM masts? Will I find enough other sails compatible?
The question as to whether the bend curve is compatible with my weight and conditions seems to have been answered.
from what i have read - SDM recommended for heavyweights like us
i have NEVER even tried an RDM
bigger question - how will those cams fit AND rotate on that RDM ??
someone must be able to ship you a combo made in heaven for a heavyweight ??
good luck !!
From one of your earlier posts I got the impression you're aiming to progress to waves.
You don't want cammed sails in waves!
But I guess at $150 new, it will always do for blasting around when it's flat.
Over here RDMs are considered the way to go, because of their durability, the people who break masts report less frequent breakages with RDM.
Not specifically looking to get into waves, just up and planing.
That is the type mast specified for that sail, but by going down this road I'm investing in a flexy top RDM and the question is, "Is that the type mast that will work for me at 97KG and going forward with other sails"
okay, even i looked at www.hotsailsmaui.com/2008/pdf/gps.pdf and confirmed this sail takes an RDM !!
this page also says --
Note: Heavier sailors over 90kg (200lbs) should use a 430 bottom and 400 top on the 5.5.
Note: Only Hot Rod RDMs are recomended for sails requiring 460 or longer masts.
So, ONLY HOT ROD RDMs over 460 AND there seem to be some warnings about heavyweights
Should beaglebuddy go for it ?? will it work for a heavyweight ??
my concern is : even if it is the right mast - you will NOT use it for any other sails - from what i can see !!!
Update; This 8.0M sail has a luff of 496, only a used 460 Hotsails RDM is available, so it will be the 460 with 36 CM extension on a Chinook 48CM carbon skinny extension, thus making the mast a bit flexier.
Apparently this mast is a bit older and made in NZ, supposed to be very durable. The new ones are made in China and have been breaking.
Have a look at the thread 'Various brands' mast flex or curve' thread over in Gear Reviews forum.
I've been on Hot Sails for years and invested in the Hot Rod masts. Unfortunately there is no longer an importer in NZ so I am thinking about my next purchase (a 6.7 to 7.3 that rigs on Hot Rod 430). What I have found so far (haven't tried any out yet) is most brands with Flexy top masts are not dedicated to RDM like Hot so recommend SDM on bigger sails with very little info out there on whether RDM is OK, watch out as the bend curves are different on RDM and SDM for some of the brands too.
I think if you go Hot with a 460 mast you are more likely to be locked into Hot Sails than with smaller sizes. Perhaps not an issue at all if your in the US as they seem to have a great online shop with good deals offered and you shouldn't have import hassles with customs clearance/duty etc.
I've switched from soft top masts/sails to stiff top.
In general terms, the soft tops I think have more wind range in variable conditions in that you can kill the power at the top of the sail and use a bigger sail in stronger conditions.
Thing I like about the stiff top is that I use a smaller size sail but the wind range is less in variable conditions.
That's a bit of a generalisation, but its the reason I switched.
