I second laat2's recommendation that you visit the laundry forum. I've been reading those posts for a few weeks as I prepare to buy a new washer/dryer set. You'll find enough information there to make your head spin. try_hard

Your Oxi product pictured is a powder, yes? As stated in responses above several years ago, the instruction is based on an assumption of liquid detergent and powder oxi ... which combined can form a chunky/goopy mixture that won't properly dissolve and flush out of the dispenser drawer or cup. Don't combine any liquids and powders together in a dispenser cup/reservoir that holds the dosage for the dispenser to be flushed with water. A frontloader detergent dispenser (and some toploaders with a drawer dispenser) typically has a reservoir cup or a dam piece that holds liquids from running out prematurely, until the incoming water flow overflows the compartment and flushes out the product, then (usually) a siphon tube drains the residual water. The cup or dam is removed for powders since they won't run out the back, the powder sits in the compartment until the water flow flushes it out (overflowing the cup or hold-back dam). A heavier goopy combination of liquid+powder sitting in the cup or blocked by the dam doesn't flush and/or dissolve readily. If you're using liquid detergent and powder oxi (or powder detergent and liquid oxi), then do not mix them together in your frontloader's dispenser. Liquid detergent and liquid oxi, or powder detergent and powder oxi (with the reservoir cup or hold-back dam removed) can be mixed together. If you're not sure, then follow the oxi directions and place liquid or powder detergent alone into the dispenser, and liquid or powder oxi directly into the drum.

I have not had any rust on Speed Queen top loaders and we have at least a dozen of them in different places in the country. These are not in climate controlled areas and no one is making sure the lid is open. They are used and abused and a lot of chemicals are used in the wash. Some are 10+ years old. My SQ TL at home probably has the lid down more than up because my laundry area is tiny and I use it as a folding table but I never even think about it. No trace of rust anywhere and I think it is about 6 years old.

Cannot speak to longevity as it varies so much it doesn't seem to matter which brand anyone buys. The one thing I will say is: if you are going with a front loader it is dysfunctional to buy one without an internal heater that will give you a true hot wash. I would check the stats on GE and Whirlpool. Bosch, Asko and Elux do have internal heaters. But again, check specs for each machine carefully. Also look for Allergen cycle as this will guarantee a 130F wash. I have owned Miele, Bosch and Asko compact sets. I would stay away from Asko as I don't feel the cost is warranted, the water level is very low and while it was great on very hot washes it was lacking on delicates and the less robust cycles. I need those for exercise clothes with elasticizers and for athleisure garments which are synthetic. I do a lot of "light soil poly" loads. Currently, I have a Bosch 500 set. Very happy with them. I do about 6 loads per week, sometime more. I have the condenser dryer -- also happy with that. They are stacked in a laundry closet. The only caveat is that the door needs to be open while the dryer is running. They are very quiet. Others are happy with Electrolux. Miele is a heavy duty machine and wonderful but there is definitely a premium in terms of cost. One strategy is to go with Miele, pay the price and figure on many years. The other strategy is to go with something like Elux and then if you need to replace in even 8 years the two sets are still less than the single Miele set. I would have gone with Elux but I needed a washer than plugged into the dryer due to the set up I had so Bosch it was. Loved my Miele but, practically speaking, Bosch does the job.