I've been told that the front forks go at about 30k

I haven't worked up a service schedule for the SV's suspension yet, but I'd expect a clean and oil change every 15,000-20,000km and a periodic rebuild.
The Beemer has the shocks changed out with a pair sitting on the bench every 20,000km (that's about two months) and I do whatever needs to be done. At 30,000km without any attention they'd be a soggy pile of mush.
At 50,000km I couldn't imagine that there'd be much of anything left on either bike.

It is a lot cheaper and easier to look after suspension properly than it is to let it go until it is spent and possibly damaged.

Cheers