I have a nice tank to cleanup before I paint it. I can see no indication of rust inside. I am experienced with both POR-15 & KBS-similar if not same products & I but KBS from a local AP store-KOI- off their shelf so no shipping & handy. Like many, including Snowbum, I'm no fan of Kreem having had to dig it out of a tank. What is the red coating used as OEM? I am looking into RedKote and have emailed them with questions. The Caswell kits are more expensive than other routes. The RedKote is lots cheaper on ebay than form mfg.. Seems I read that the BMW/OEM is a good choice on nice tanks with little to no damage inside as easily redone. I searched some here & google but still have questions. What say the "experts"???