As you can see in the screenshot of my inventory, I have been fairly successful lately with invention. Got all the related skills at 4 now, and the hit / miss ratio with the drones has been a lot more hit than miss . I also invented a few Ballistic Control Unit II bpcs. Those and the Hamerheads seem to have a success-rate of about 30%, the hobgoblins are lot higher, I would say 70% or so ?

Luckily I found a backwater Gallente system that only had 5 days or so que time for copying blueprints. Our alliance has some laboratory facilities, which is fine for ME research but copying is still buggy or cumbersome, so I was told. But it didn’t matter too much as I needed the time to get some more data-cores from my agents. I now have two electronic engineering and two mechanical engineering agents, which gives a nice source of income as well, for the cores I don’t use.

Overall I wouldn’t recommend doing this all, as it doesn’t seem to be worth all the trouble. The past week I produced drones from the above mentioned bpc’s and am now selling the Hammerheads for around 1.1 mil. The hobgobs go for about 200k. So I might as well hang on to those. The producing part is a bit of a hassle as well, as you need these weird parts (and you have to produce the t1 drone as well) and have to travel quite a bit to get the best deals. It’s fun to be using your own drones though, and the investment wasn’t that bad since the price of the data interfaces and encryption skills have dropped considerably. Which is of-course the reason why there is so much T2 stuff on the market at the moment. But if you got a few million isk (and then some) to spare and want to see how it all works, and you have an industrial character, feel free to give invention a shot.

I have no idea if the starship production is more profitable. Probably also in bigger numbers as the starting investment is a lot higher. The starship interfaces needed are a lot more expensive.

There is an interesting analysis on the Eve-O forums that agrees with my point of view :

I would persuade small-time inventors to stay out of the business (unless it’s for personal use in remote areas of the galaxy) for the time being, because they tend to ignore the long-term (average) costs, and usually undersell their “lucky chance” products, only to hit a bad bump when the unlucky streak starts. You’re really better off just buying off the market most of the time.

Due to the chance-based nature of invention, I would recommend that you ONLY go into invention at all if your skills are good (L4 each of the 3 relevant skills) and you have a starter capital that will cover (on average) at least two, preferably three successful invention jobs per “investment batch”.

And ofcourse the invention guide if you want to get started or just see how it works.