I'm curious to hear from fellow Nissan enthusiasts about performance upgrades. I've been considering a few mods for my R35 GT-R but want to know which ones are worth the investment and which can be skipped. Are there any notable differences in power and handling when adding something like a cold air intake versus a high-flow catback exhaust? Should I focus on engine-related mods or look into suspension upgrades as well? What's been your experience with performance upgrades for your Nissan, and what did you find to be the best bang for your buck?