Why don't you list the chemicals in the Simplicity system?
Most of these packages are just fancy re-branding of standard stuff, with some additives you don't need or want.
If it's Bromine or Bacquacil, you have a decision to make.
But if it's just a chlorine compound, you can "switch" to B-B-B tomorrow--or today. You aren't actually switching--you are just buying the products you need far cheaper and only when you need them.
pH-Up! from Biogard is nothing more than sodium carbonate--Soda Ash--Arm&Hammer Washing Soda (not baking soda) is the same stuff.
Most commercial pH raisers are soda ash--and expensive.
20 Mule Team Borax is far cheaper and has fewer side effects.
pH-Down and other powdered pH lowerers are nothing more than dry acid--buy it as cheap as you can find it generically, or use Muriatic acid, which has less side effects.
Total Alkalinity Raiser is Sodium Bicarbonate--Baking Soda. You can pay $12 for 4 lbs, or you can pay $4 for 12 lbs at CostCo.
Chlorine is chlorine is chlorine. Liquid Chlorine, aka, Laundry Bleach has the fewest side effects and is usually cheapest. Don't buy the hype about it adding Total Dissolved Solids--the salt for a salt-water generator adds at least 10x as much with no problem.
There's only one algaecide that isn't more trouble than it's worth: Polyquat 60%...If the bottle say Poly...<something>... 60%, that's the stuff, no matter if it's called Black Algaecide, Mustard Algaecide, etc. Don't pay more than $15/quart if you can help it, $20/quart if you gotta have it now (anything higher is a rip-off).
The other algaecides can cause foaming, clouding and lots of other problems.
Other stuff: Clarifiers, sequesterants, flocculants, bluing, etc. Avoid them like the plague. You only need them under specific circumstance and most people NEVER see those if they follow good maintenance discipline.
Testing: If you don't have a good test kit you need one. Even the 5-way drop test kit from Wal-Mart is better than nothing. But a true FAS-DPD chlorine test kit will pay for itself many times over even if all you have is a 15' Intex Donut. I bought my first FAS-DPD kit when I had a 15' Intex and I was AMAZED at how much it helped.