I have an 04 berg and have had .50 springs in it with weight on the front end doing touring , it barely used 3-4 inchs of travel under normal riding/touring offroad.
If I had my time again, .44 or .46 would have done. You can only get so much weight on the front of those bikes.
my rear spring was the next heavier one up from the standard one it came out with.Me ( 100kg) If you are just putting another 20 kg(and you being 80kg) on the back of the bike and not riding hard and touring, I found you could get it ok using clicker ajustments.a bit out on the rider sag though.
I have just purchased a Race Tech SRSP 6326 P30 rear spring( what ever all that means), thats a progressive spring. I found the first 2 rides a bit strange,it sits up well in the rear and can get sag right now. I have backed off all the rebound and compression almost. After about 20-30 minutes of riding, it seems to come good, it has a fluffy or softish 3-4 inches, then when a heavier compression of the spring happens it seems to soak it up well with out tending to completely bottom out the shock.If you done some internal work on the PDS, maybe it would perform even better? I have .46 springs in the front and it has given back balence to the bike.
The .44 front springs were running low in the stroke ,normal riding making it harsh over rock, the .46 set up does not compress and slow the bike like the .44 springs under excessive braking, how ever it does not deflect over rock so much now( 4-5mm preload, 130mm oil gap). It does have a tendancy to slide the front a touch as I did like it to turn precisely or sharp before. When i get time i will loose some more oil out of the front, then try less preload on the front and see if it will turn a touch better. Forks are already up in the clamps 6 mm and use all but last 20mm of travel at the moment.
Very limited experience on suspension to.
All that info may not be much good as i think 05 had changes in suspension maybe ?
) unless you go for a revalve as well it's better to have it a bit softer and more compliant given its a long distance trail ride, so I'd pick .46 up front and even 88 on the back.
