I have a Maytag front loader and don't like it. My old washer was a 16 year old top loader which worked well but small load size. I actually miss it. I end up only using the extra load capacity on rare occasions. Plus, I could do a soak and strip in the top loader where as I can't in the front loader, something I really wish I would've given more priority when shopping around.
I use the Persil + Oxi detergent in the same amount each load. I change the soak time depending on what I'm washing. The more soiled the clothes, the longer the soak. This is based on my own experience getting mud and food stains out of kids clothes and oil/grease stains out of my own. Letting them soak for an extra 20 minutes does a lot more than extra detergent. When the clothes are really bad, I'll strip them (Persil + bleach + borax) in a bucket for a couple of hours