same here, but i think on my next batch i'm gonna go 4:1 as there probably won't be a big noticable difference. also, this has to be one of the most economical dressings out and i primarly use it for the wheel wells and the dilutions make it a excellent bang for the buck value, instead of some of these other gallon dressings some sell that are ridiciously priced (over $30) that aren't dilutable. i also use the apc at 4:1 as the 10:1 ratio is a little to light for my use...
There's not a *huge* difference between 3:1 and 4:1 on the Hyper Dressing; the biggest place you'll notice the change is on tires.
Most of the tires I tried using it at 4:1 on, they really didn't like it and I'd have to reapply. 3:1, no issues, 4:1 they'd look 'dry' or go blotchy sometimes, even after wiping them down.
I finally bought a gallon of Meg's APC+ and the label on the back suggest 1:10 for medium cleaning so a general wipe down could be 1:20? This is similar dilutions recommended by DG for their APC. Maybe 1:20 is "Quik Detail Spray" cleaning.
For tires, HD at full strength is the only way to go for me. I saturate a small dish sponge with 3-4 tbsp. for all four tires. And it LASTS. Even at full strength its fairly economical stuff–by the gallon anyway. If you only used it for tires, you could dress more than 80 vehicles. For wheel wells, engine plastics, etc., 1:3 works well enough. 1:4 or higher dilution it becomes pretty worthless if you ask me.