you won't regret the Raystorm choice I love mine! it provides good temps and also tends to look awesome with acrylic bracket and LEDs (2 of them come standard). MCP35x is a very decent choice with the huge head pressure it gives, however for Raystorm even a standard D5 works great. I use a D5 Strong here at 24V, that coupled with 2x 670 Razor blocks and RX240+EX360 rads. can't complain, this setup performs awesome (if not for my hot room ambient temps) and looks amazing too
Don't go with RS series rads, they are cheap and thin with a high fins count, that means you will NEED high speed fans for them and that means hella loud setup. Take RX (very thick, low FPI count at 8) or EX (half the thickness, FPI count in teens). I don't know the latest AX series, not sure what it provides.
A friendly advice, flush the XSPC rads before use! I failed to do this and RX rad was spilling some whitish stuff into the loop during initial use ... also never go wtih Primochill's Primoflex LRT tubing, it plasticizes like hell (ask me how I know), if you want colored tubing (e.g. UV reactive) then go with (German) Feser UV Active or new (they seem to fix the problem) Primochill's Advanced LRT (only UV Blue at the moment, other colors are solid and non-UV reactive).
I would definitely go with reservoir above the pump, even though you could run some setups without a res, it's highly recommended to have a fill port right above the pump, so it never runs dry (it damages the pump after a few uses on dry air).