Question about TETRA PRF 1500-2500 pressure filter.

I am thinking about adding another filter to my pond. I have a Tetra
PF-3. The PRF 1500-2500 models are pressurized and they say you can
back flush em. Does the backflush work well? It looks like a pretty
big canister filter and those are a pain to break open and clean out
all the time. I remember having to clean out my Fluval cannister
filters for my indoor aquariums and I can imagine the horrendous gunk
that could accumulate in an outdoor cannister pressurized filter.
Help, I don't want to spend a $150 bucks for a filter that does not
back flush well. This filter does not have a built in pump right? If
not I can hook it up to a pondmaster pump with a nominal strainer in a
mesh bag, would that work? Thanks a lot and if you have one of these
Tetra pressurized things do you like it? and is the backflush feature
any good. thanks again--------
steve