Mine has a braced swingarm, not sure if Monster or 851/888 but an original Ducati made one.
It was not without problems though as the bracing was very 'tight' on the chain side and the chain sits close to the tyre so I had a problem with the chain bouncing between the two and eating into the bracing.
After repairing it, I made a stainless steel guard plate for the brace but then the 'bouncing' actually cracked the brace where the guard ended so I widened the bracing and all seems much better now.
Also it had similar scarring to the one above but all that can be repaired by welding/grinding etc.
I did keep a spare standard ally swinger that I initially had as a backup if required.
Swingarm (with unsuccessful chain guard in place);
As per Utopia's comments, I don't think there's much weight difference between ally and steel and I would say the braced ally would be heavier? and I'm not sure how much difference the bracing makes to handling etc. but I suspect none that a mere mortal could detect - looks good though!