Surprisingly because the most expensive cars on the US market today are also the ones whose owners are most likely to lure upgrades to the secondary market, the urge to make expensive toys is just a little cooler to overcome.

When it comes to aftermarket BMW parts, there are some upgrades that are relatively easy to implement, even for DIYers, and push productivity, or at least perceived performance, to a level that makes the extra time, cost and effort worth it. You can easily buy performance exhaust systems for your car online via Xforce.

For an easy upgrade, the second market muffler is truly unbeatable for enhanced gas response and rumble display and sound effects. The overall weight reduction of the system also seems to increase overall torque, giving at least the illusion of more power. Against the backdrop of the benefits of installing an improved exhaust system, there are minor drawbacks such as system background noise, which while still road legal when travelling on surface roads, is worth experiencing the full power of acceleration in the open air.

Also high on the list of potential downsides to installing multiple secondary purchase systems is the tendency to make pre-installation modifications to ensure a proper fit or at least a fit that doesn't require adjustment after several heat cycles. 

Of course, there are several systems on the market that have a different look after installation, most look great and will do the math to increase horsepower to the mid-range, although most don't retain their sound power at full speed.