HELP ME GUYS ...i'm desperate

Ok, im from europe (more exactly portugal) and i'm about to buy this new computer , hopefully a hard gaming one. Here's the thing, this guy told us about DELL, it was very good, costumer service 5 stars etc. And i happen to know this german company really good one called ATELCO, wich has really good prices and great service. So, my computer aint gonna be only mine, i have a bigger brother and now he's obsessed with DELL. But i can get a really better rig in ATELCO then in DELL. If anyone has had experience with any of the companies plz tell me how it was. plz

Thank you guys for the tips, i hope i can enlighten my brother's mind now. Btw the ATELCO pc i have in mind to buy isnt a pre-built one (i dont like buyin pre-built ones either) but like there' a configurator to choose your own parts and theyre quite cheap, for example hopefully in atelco im buyin the basic i7 cpu model for about less than 250 euros. u can choose then if u want them to build ther and send it to u or if u want tha parts and ull built it urself. u can also open the pc and change parts that the warranty wont go away. it will still stay the same, and its about 5 years warranty.