Hmmmm I can't remember regretting any hardware I purchased. I tend to do a lot of research before buying hardware because well... I'm not a rich guy and hard earned money needs to be spent wisely. I read reviews, ask around and go to stores I trust. Sometimes, I spend so much time doing research that when I decide to purchase the product, it's already gone! LOL
Before, I usually get this itch of upgrading my hardware up to a point I know I don't need such as getting an i7 to replace my unlocked i5. I don't edit videos and do heavy photoshop and so on. I would probably regret upgrading! If we talk about ANYTHING, well... it's got to be the coffee maker I purchased! The pot broke after 3 weeks X_X