Best domain/subdomain setup.

Perhaps a stupid question...but I just want to be sure which is best.

Example:
I wish to push a particular product lets call it an "epsonprinter"
I manage to buy

Code:

www.epsonprinters.com 

(note the "s" on the end)

Now, I have topgen and want to generate pages for each particular model of epson printer..... So questions:

1. How many sub-domain would you recommend to have on the same domain? Should I mix the domains (on different ips also) or keep all in the epsonprinters.com domain/sub-domain? Is there a limit to the number of pages or sub domains you would recommend?

2. format of the subdomains.... Example Epson Stylus R300 printer
what should the sub-domain be named?
a)

Code:

www.epsonprinters.com/epsonstylus-r300

b)

Code:

www.epsonprinters.com/epsonstylus_r300

c)

Code:

www.epsonprinters.com/epsonstylusr300

THanks in advance for any answers and advise you can give, heres hoping it also answers the same questions for some others

 

Anyone recommend what is best?

 

If i look it at a SEF view of it, go with A i would also change up the Epson-Stylus-R300 spiders cant read EpsonStylus

 

Thankyou for answering
So domain should be

Code:

www.epsonprinters.com/epson-stylus-r300

I will be using topgen softweare to generate the pages so:
How many sub domains is it ok to put on this so google etc dont flag it?
How many pages would you recommend, 50, 500, 1000, 5000? for each subdomain.
Should I have them linked between the sub-domains as well or not?