I have an old Rena XP4 (API Filstar now)..................nice price point, very powerful,quiet, versatile (can hold TONS of media)...have 1 one my 125GL & it runs like a champ.
Eheim are VERY expensive, & they are no longer made in Germany....Made In China now, I believe.......not sure how they justify that high price anymore....flow rate not very powerful, makes a good biological filter, not so much for mechanical. IMO, I wouldn't pay a high price for a filter that's Made In China. If I wanted that, I would get a SunSun piece of junk for far less money.
If you have a huge aquarium, 180GL+, get a Fluval FX6. VERY powerful, well worth the money.