All corys breed basically in the same way. Google up 'How to breed Corydoras'
Corydoras Weitzmani are often very expensive for corys (£40 each at my LFS) so you'd probably get a nice little profit.
As for if they are worth it, unless you are gonna breed them, there are nicer cheaper alternatives
Price wise differs from place to place... cheapest ive seen them for is £8 and the most expensive £18.99.
Breeding 'all' cory's arnt easy in the slightest, im sure coryologist and coryman will both confirm this with species not even been bred yet. If all cory's were easy to breed then there would be an abundance of cory's around and the prices extremely low.
Weitzmani are not the hardest cory to breed by a long shot but there are also not the easiest. The breeding isn't usually the problem, rearing the fry is far harder and some species are just extremely hard to rear.
Anyways good luck if you decide to buy and even more luck with breeding them