I've got one and they are great deals.You need to get one that has(believe it or not)the Special Weapons stainless steel receiver.The S.W. receiver has the paddle sight rear sight and the Hesse has the drum rear sight.
The wood furniture is great looking on these.Accuracy is OK,for $500 bocks you can't expect sub MOA.I mean I don't expect the same results as I get out of my $1500 AR10.It should come with 2 20 rd CETME mags.They are curved instead of straight like the HK 20 rd mags.
aimsurplus.com did have the 20rd mags for 5 for $100.Usually they run $25 each.The only problem you might find is there's not enough adjustment in the front sight when you zero it in.Century,the manufactore,had a problem when they 1st built these.They will fix it if you send it back no questions asked,no charge.I sent mine back and it cost $10 UPS and I had it back in 3 weeks.
Don't let this scare you,as you are getting the very reliable HK operation(delayed blowback)for a fraction of the cost of a HK.You will not have a "REAL HK" but you won't pay real HK prices.
I would certainly buy another if I could hide enogh stash money from momma.Check out HK91.com for more info.