I haven't had much experience with many filters, but presently my favorite is my Cascade 1000. I can almost guarantee it's not a popular choice but I think it's because of it's low price that not enough people give them a chance. People assume that the more money you spend the better the product, unfortunately that's not necessarily the case these days. I've paid more for my Fluval and Rena and in my opinion my Cascade out performs them both. It's extremely easy to prime, I've never had it leak on me(knock on wood), comes with a spray bar and it's very easy to take apart clean and maintain. I was actually forced to buy it as I was low on funds and had an emergency situation caused by 2 Fluval canister failures in a row. When my third Fluval went I bought another Cascade to replace it and they're both functioning reliably ever since.