YES, It is "OK" to spray "dry" on 08 Busa's. I'm quite sure with a little ingenuity you could get the 1LB bottle in trunk, Although i would venture to say a 2LB would fit better(because of its shap and size...short n fat)but i myself have not done it. As far as whats the best brand, your gonna get alot of different opinions, i MYSELF, have ALWAYS had good luck with NOS, but NX, Zex, Nitrous works and any other BIG names out there, you'd probably be ok with.....remember, there can be one bad apple in any bunch! The most you can spray on a "stock 08" varies to much on who, how, and what patrs you use to tune it, i personally wouldn't spray no more than a 80-100hp, and i'd be damn sure to have my AFR(air fuel ratio) dyno confirmed and or wide band controler...shutz n2o off if it goes too lean. OK, "PC or bazzaz"?, well again......loaded question, DEPENDS ALOT on what your wanting and parts to dollar ratio! If your a "weekend warrior" and just want a 30-40hp kit to go yheee-Haaaa with ounce in a while, you would be just fine with PC3R, you can get the hub switch(only way you can run 2 maps)and have a 2nd fuel map for n2o. If you have the money(about 900.00)you can get the bazzaz, it has the capability to run all (8) injectors and "self maps" for a target AFR. My PERSONAL advice, id stay with the PC3R, alot of knowledgeable people out there of this set up, and here shortly dyno-jet will have the capability to do everything bazzaz can do!
NOW, should you spray "dry or wet"? JMHO here, but starting out not having alot of experience with nitrous, i'd recommend DRY for you all day! its relatively cheap, simple in how it works, stay small(30-40hp), get a GOOD TUNE(AFR setting), and GO HAVE SOME FUN! I sprayed a 50-60 dry shot on my Z12R for years(100+ bottles)and never had a hick up! I'm going to spray 40 dry on my 08 busa(after going back and forth 50 times between wet or dry?
) and all i'll be using is Gixx's spray bar
PC3R w/hub switch, and as soon as i can a wide band controler. Anyways, you will probably get a different opinion for every single person that replys to your questions, this is mine.
BTW, The guy i would listen to THE MOST would be GIXX 1300R, awesome guy and knows his chit on N2O. Hope this helped