This thread sums up the current state of what happens when you combine broken automated systems with sellers who don't set their listings correctly. Sellers then blame eBay for making it too complicated while eBay blames sellers for not setting things right. At the end of the day we're the ones getting screwed paying more for less and I'm pretty tired of it. The cost of living and operating in Canada is already out of hand and buying stuff on eBay is turning into another one of those "Nope can't afford it anymore" things.
Basically, with eIS, every purchase under $50 that you make is money down the drain. With GSP, you could buy $150 of stuff and in a lot of cases still get buy with a $50 shipping fee, but this is downright impossible to achieve with eIS unless you're making only single item higher-valued purchases that are light in weight. If you're buying anything worth under $50, and if you keep track of the numbers like I do, the overall shipping costs from cumulative purchases made via eIS are just downright atrocious and unsustainable.
When you're spending more on cumulative shipping costs than the goods are even worth is when I draw a hard line. These days I typically still try to operate within a 75/25 rule in that for $75 worth of goods, I shouldn't be paying more than $25 of shipping. With eIS, each cumulative purchase puts you into the red in terms of your overall goods:shipping expense ratio and my overall expenses on shipping are to the point where I likely won't buy anymore volume until this supposed combined shipping is implemented.
