Gday Ben,
The new stella's are pretty sweet that's for sure, but the old ones are proven and will still handle the same fish.
Put it into perspective, nearly all the enormous GT's caught on Nomad and by Okubo (Legend 5 dvd) were caught on a dirty old 10000 Stella. Yes some of them use bigger spools, but I don't reckon it's necessary in Cairns. The 10000 was certainly good enough for them before the new version came out.
There are heaps of GT's around Cairns, but I can't say I've seen one yet over 30kg. Even if I did I'm pretty confident in my 10000. Any GT that can spool a 10000 in Cairns will reach a bommie before you reach the spool knot. I was using an 8000 for ages and it caught plenty.
You should be able to get a 10000 pretty cheap at the moment too, though may have to look further than the local shops.
Those new ones are nice though, depends how much you want the latest gear.
cheers,
steve