Thanks for a well written, clear and concise review!

I'm a photography student and although we have access to the school's studios it would be a great advantage to be able to practice with lighting any time at home.
My idea is to
not buy the cheapest studio flash system there is, but something which I can afford now and also use professionally later when I start photographing for a living (I've also considered getting a system where I could use my Canon 430EX flash with a softbox, but as I've found out those solutions are too limited, I would most likely need to buy an additional handflash anyway for such a setup, and those systems aren't really dirt-cheap as I had hoped for, so I might as well go for something more professional, versatile and lasting and see it as an investment), and then add extra flashes, softboxes, barn doors etc. as I need them.
The BXRi "to go" set seems to be a good choice, but with limited knowledge I want to make sure I don't make a mistake.
I've followed various discussions where people recommend people to buy the FX instead, which confuses me, because I don't know if that's because the FX is the most advanced flash there is with "expert options" (that I probably don't need anyway) or if the BXRi is "so so" and not considered something that professional photographers can use -what do you think and are your experiences?
Also, I don't quite know what I need in terms of flash power and additional gear. Currently, as someone new to lighting I will mostly be expermenting with still-life to learn about shadows, lighting from different angles, diffusion, soft/hard light and so on, but will probably also photograph people and other things. I don't know what I will specialize in when I'm done at school, but I suppose it will be a little of everything even though I currently have a main interest for product and food photography.
When asking someone more experienced than me about getting the 250 Ws, 500 Ws flash or a combination of both I was told that for product photo even 500 Ws was barely enough because the aperture is usually very high (f22 etc.) thereby restricting how much light the camera's sensor would receive.
Is this true? Flash units in the 1000 Ws range or higher are much more expensive.
At first I was considering getting a set with one 250 Ws flash and one 500 Ws (I read somewhere that you often need to lower the light a lot, and many flash units won't go low enough meaning you need to lower it further with neutral density (ND) gels, so looking at the technical specs the 250 BXRi I see that it goes lower than the 500 BXRi. It's also got a faster flash duration than the 500 Ws model. Then again I don't know how much this matters, and I'm concerned about not getting enough power for still-life use.
Any thoughts on this and other things I need to consider?