OP's budget is 1,000 euro (that is $1,500 US) ...
- BSW stage 1 package is $519.99
- BSW SubWoofer System is $729.99
- BSW amplifier upgrade is $699.99
So OP it is up to you to decide which is economical... I'm very sure you get a better package price if you get all 3 packages...
Don't get me wrong I'm not hard selling BSW... I just think it is a good set-up for it's price...
INJEN DCI / AA STRUT BRACE / KW V3 / HRE 797RS - NITTO INVO / OEM M3 HOOD / M-SPORT REAR BUMPER / MACHT SCHNELL DP / ER FMIC / TurboSmart BOV
(FUTURE MODS: JUICE BOX 4 - G5 / AKRAPOVIC or MEISTERSHAFT EXHAUST (UNDECIDED) / AWRON DGA GAUGE / STOPTECH BIG BRAKE KIT / TOP STITCH CUSTOM INTERIOR