Retailers generally sell the latest tech
If you walk into any Target or BB, you are going to find newer products because that what's in demand and what brings in more of their revenues. With all of your devices that support only SD and not SDHC, you look online. Been there, done that. Now sometimes a rogue brand has issues, but it's not that common. Smaller capacity cards are generally much easier to accommodate fully with legacy devices than larger card sizes are with newer ones IME. Keep in mind it's really carrier software limitation sometimes vs an OS limitation when you encounter an upper limit to what capacity SDHC will be supported.
You are also missing the boat partially when it comes to performance in some cases of a quad-core rig single or dual core. If you push out a device that has a stellar AMOLED screen and can play back 1080p video, you might see the benefits of having a handset with ample RAM and a quad core CPU that never, ever stutters. This might be as simple as one app being updated and written to support the particular handset with a quad core under the hood.
My impression was there may have been other reasons why the Tegra 3 quad didn't test well initially vs the dual core snapdragon ATT was running in their HTC when they were compared. It certainly isn't anything nefarious such as 'the Android OS simply won't properly support a quad core processor'. That seems to be the jump you have mistakenly made in this thread. Issues such as what functionality is bundled together with a particular chipset vs what another manufacturer does on theirs comes into play when comparing speeds & performance at testing time.
I honestly wonder though- how many mobiles running W8 will have to have quad core chipsets(?)