I've found the biggest problem with stainless steel tanks is that the lid's get mismatched. Tanks and lids do not seem to match well across brands. I have a couple of older Nikor tanks where the lids are original to the base and no problems. Same issue with the top cap.
I've also run into problems where the "aftermarket" plastic caps fit one brand of base and not another. Sometimes they'll only go on with difficulty, resulting in premature cracking.