We don't recommend prefilters.
Why don't you recommend them? Do they not pre-filter, or do they not reduce maintenance on the 'real' filter?
I was about to post this same question but searched and found this thread. I'm doing the same thing as islandtees except coming from a sand filter. I'm in the woods and get an amazing amount of debris in the pool. If this saves the cartridges in the DE filter I'm installing, I'd consider it.