I have a 265gal and 300gal tanks and I would recomend using 2 aquaclear 500's (called 100's now) and a wet/dry sump.
I know they cost a little more but it is the best way to get good fitration and bio.
I have 3 xp3's that I would sell. I used to use them but I have found that aquaclear and wet/drys are the way to go.
3- 10 gal
3- 20 gal
2- 29 gal
2- 55 gal
3- 75 gal
2- 90 gal
2- 120 gal
1- 125 gal
1- 135 gal
1- 265 gal
1- 300 gal