Greetings
I am looking for a new skimmer and asked the same question a few months back. I learned very quickly that many people are very passionate about the type of skimmer they favor! I have never owned a Lifereef product, although I have owned a venturi skimmer (CPR) but I traded many emails with the owner while doing some research. Here is what I found:
1) Lifereef products may appear to be "pricey", but most will tell you that the crafstmanship is superb
2) The owner is very helpful and the customer service is excellent
3) Many people consider venturi skimmers to be "old school" and newer types (Beckett, etc.) to be vastly superior
4) Venturi skimmers are pretty much "set it and forget it" devices. Newer skimmers might do a better job, but that comes with a price (more pumps, more complexity, (generally speaking) more tinkering and tuning, etc.)
If you want a quality product that does what it is supposed to do with little tuning, a Lifereef skimmer might be a good choice. If you want to skim the livin' crap (literally) out of your system and don't mind tinkering with the settings, then look at newer technology
Just my 2 cents - hope it helps...
Good Luck