Have installed progressive fork springs and replaced fork oil with 15w on my 09 Touring.
Huge difference to handling front feels much more planted and stable under load and you seem to glide over bumps much more. All in all a worthwhile mod for not too much outlay.
Could not believe what a difference the Progressive 440 rears made. Night and day difference. Perhaps the best mod so far. Took the bike in for front springs but the dealership lost the front spring tool so had to order another!