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Quite acceptable coffee can be made on the cheaper machines if you work on coffee quality, freshness, grind, dose and tamping.
The grinder you use is very important.
I think the 800 has a dual walled filter basket. Get a single walled basket if you can. Dual walled filter baskets are made to get fake crema when using stale coffee.
I did use a BES860 and with some modification to the built in grinder I got acceptable coffee. I have now upgraded to the dual boiler BES900 and I am enjoying it.
Have a search and see what others have posted on this site about the 820. Let us know how you are going and ask us here for further help.