Sometimes i start to collect series in regular TPBs but then later they come out with a hardcover so i sell the TPBs and get the hardcover then later they come out with the big complete collection TPBs which i love so i get those and then even later there might be a Omnibus. Since i kept buying and selling the same stories over and over again i now started to keep the series i love in multiple formats but that is just a giant waste of space and money but if i sell one of the formats i know i will regret it later. For example i have Kurt Busiek and George Perez Avengers in floppys, in oversized hardcovers, in TPBs and in Omnibus and that's just one out of many examples and now i am running out of space. I mean there is more spcae but i don't wanna use more for this hobby in our house but i just can't decide. I like the trades for readabilty but i like the Omnibi for the bigger art and the better paper quality.