Looking for some opinions.I would like to buy a bulk oil in a drum,the amount of cars owned by family and friends is overwhelming me when it comes to buying oil.I am using 50-80 gallons a year. This is a partial list of cars,none are used for long daily commute just around town so i guess severe service schedule would apply. 99 Ford Expedition 5.4 2V owned since new,98k with 3k OCI with dino,no oil usage and spotless inside,compression like new all 8. 2000 Poniac GP 3800 80K,bulk dino every 3K,last 4 yrs on GRP III valvoline 5K OCI super clean inside with no oil usage,compression good. 95 Toyota Tercel 92K,Mobil 1 0w-30 last 4yrs once a year OCI approx 5K,showed signs of neglect.2X ARX and mobil 1 seems to have cleaned it up nice,ARX improved compression to almost new. 2000 Toyota Solara 105K 3.0 V6,not sludged,was clean,ran Amsoil SSO for 1 yr OCI approx 10K on this one and see signs of varnish,switched to Mobil 1 for cost reasons and dropped to 6mo 5K OCI and 1 ARX run.All looks good now. 2005 Honda Oddesy Touring 3.5 V6 80K around town(soccer mom),bought new,brother ran 2000/SSO since first OC 10K OCI and its in trouble,lots of deposits and varnish.Running ARX with valvoline now,compression lower on all 6,2 are lower. 2006 Infiniti M35 3.5 V6 54K exactly same 10K OCI as Honda above.SSO w/deposits and varnish etc overall lower(not low) compression. 2007 Saturn Sky 2.4 L4 non turbo 6K.changed all factory fluids(oils) at 1K lots of particles came out,OC with Castrol edge 5w-30 2002 GMC Denali 6.0 V8 100K OCI unknown,looks clean inside compression good. 2000 Chevy Venture 3.4 V6,100k Spotty OCI(father doesn't believe in maintenance).Engine looking nasty,rear main leak,deposits,varnish etc. 1999 ford Ranger 3.0 V6 54K same as Venture just not as tired. 2000 Ford Explorer 4.0 V6 120K nasty,OCI unknown(sister like father) 2007 Nissan Altima 40K OCI way to long (sister)deposits forming etc,no maint at all. 1999 Caddy 4.6 60K my old car until last year 5K mobil 1 spotless now getting neglected. Kit car Factory Five GTM with LS7 new build 2008 Mazda 3 OCI unknown (they just got it) Kubota tractor with 3 cyl diesel Probably 10 other cars and pick-up trucks Various small engines in generators,snow blowers etc I got my father and sisters to at least let me change the oil.Its in my best interest to do it instead of doing major repairs later.My brother is 100% into keeping his cars up to snuff.Funny his cars were running the supposed best oils(SSO)and are seeing more deposits than they should be.This is nothing against Amsoil or pro any other brand just an observation of what's going on over time. The Mobil 1 seems to work really well based on cleanliness and compression test in the cars i used it in long term. I was thinking about Rotella T 5w-40 in bulk but have some viscosity concerns about winter use.MA can get pretty cold in jan. Any thoughts and opinions are really appreciated.My garage is looking like a Advance Auto shelf.We did try the Amsoil route briefly but the cost and seemingly less than stellar results have kind of left a bad taste. Maybe shorter OCI would have had delivered better results but at the price seems to be counter productive. Thanks in advance.