Enz All and PreKleen are
Chemspec products which were recently taken over by Saphire Scientific.
Good products that have fallen out of favor in the last several years do to lousy marketing efforts. ( I think )
I haven't used Enz All or PreKleen but I've used Kill Odor Plus,some TLC (traffic lane cleaner) and a few others others
and they work really well.
Do what Doyle suggested as a starting point. Get a good quality broad spectrum prespray that can be used for
light to medium soiling. Aggitate or rake it in with 10-15 minutes dwell time and extract. That should be good
enough for about 80% or more of your cleaning jobs. Then, if you need other "specialty" products pick them up
later.
Don't over-think it. You'll drive yourself nuts! There is NO SILVER BULLIT!!
Each chemical manufacture has 2 OR 3 "Blue Ribbon" horses under their roof. Find one you like whether it be
because of location, price, dilution ratio, ease of ordering, technical support or whatever,
and give them a good 4-6 month trial.
After you've got some cleaning under your belt you'll have a better
idea what chemicals you'll want or need to meet your cleaning needs and be better suited to hand pick
your products for specific situations.
Larry linked up some threads from past posts on the subject... you aren't the first person to ask that
question and won't be the last. Use the SEARCH function for Prespray.. you'll find SOOOO much stuff on
the subject you'll throw up.. seriously

.. I did!
Good luck and keep in touch,
Bill