are twin side draughts worth what you pay for them if they go alongside other small mods???

If the other engine mods are only small then I wouldn't reckon you would have to go with some twins.

If it were just for a mild street engine say with a mild cam, mild headwork etc then a single side draught should be more than enough - even a well setup 32/36 downdraught.
If its a fairly extreme engine with major headwork, cam etc then yeah go with the twins

Here is a site you (all ) might find usefull - it measures what size carby would be appropriate givin things like max RPM etc
Carby Technical Advice

Hope this helps

so if i went ofr some cam head and exhaust work would a set of twins be warrented?

well when i had 32/36 on my current A14, with head work, mild cam, exhaust, extractors etc.... i was impressed with how the it went with the 32/36, a great progressive carby

when i put the 40s on, the responsive was way better, the take off was awsome and the reving is out of this world and the sound ...... the twins are way better but with them comes cost, Tunning (dyno), then jets, air correctors, imulsion tubes, 4 air filters, regulator, elec fuel pump etc

But once thats all paid for and u have just enough for FUEL, get ready for a fun ride

p.s dont forget that webers were built for high rev performance, to be flogged over 4000rpm around tracks all day so dont expect to drive it economically they just wanna give ur Aseries a good reving all the time!

how much did it roughly cost to get yours setup?

well i got my webbers for great deal with filters, braided lines, manifold linkages and it was off a Aseries so i only had tobuy like 2 main jets that were out.

then on top of what they cost me regulator ($60), new fuel lines($ dont rember), elec fuel pump ($110), tune ($150) and a few other lil thing chucked in

price is a realative to what u need, how far ur jets are out, what condition the carbs are when u buy em, etc and how expensvie ur tuner is so price for setup and carbies can vary from like $400-2000 depending on if u buy brand new, used or abused