[tuxen]

but it says a lot about where the bottleneck lies; the sdcard memory technology so anything that can speed this up without breaking any stability is more than welcome IMHO

My own experience with a class 10 card v. USB was different. I could not discern any difference in the speed of the interface between the two (navigating was very acceptable in both).

In terms of performance, I suspect that the issue pertains more to differences from one SD card to another rather than generic differences between SD cards and USB sticks:
- there is a well known issue of Raspberry Pi being fussy about which SD card one uses, regardless of class or size;
- many people have reported significant performance improvements when moving to USB;
- others have not seen performance improvements. I recall seeing benchmarks posted elsewhere with a particular SD card and USB drive having virtually identical read and write times.

What this suggests is that you have to be a bit lucky with your SD card, whereas most USB sticks are OK. Personally, I use an old, slow 128 MB SD card for 'flash' and a USB stick for 'storage'. My reason was to avoid corruption of the storage volume (particularly while using alpha builds). Two good reasons to use USB, I think.

If you read my post you will see that on 512MB boards and gpusplit of max 132MB the operating system plus openELEC is running completely from ram so GUI performance and likes are the same. Furthermore if you have a bigger gpusplit and its loaded from the sdcard you still won't see much difference because the SYSTEM is read only again no write operations can take place in system. But I'm not talking about sequential read speed here, its pretty equal. I'm not talking about overclocking either.

I know i mixed it a bit together but I'm talking about write operations exactly as documented here with fs2fs. I'm saying in my experience a modern USB 3 stick or harddrive will give you the same or higher small READ/WRITES to the database(s) a tremendous boost in write rates than ext4 on any sdcard STORAGE partition. The storage PARTION is write able and holds your databases, again I'm not saying the GUI will fly but depending on what addons you use and you library operations in most cases the system overall will seem faster.

If just using a simple addons without metadata such as xml lists or naviups, or another simple listings addon with no metadata or fill your library with a new tv-shows I agree not much speed can be gained switching to a faster storage media. Apart from the overclock trick some use because they have corruption with their sdcard at to high speeds.

And I totally agree with you on the sdcard's plus specific pi can lead to corruption. I'm highly aware of the experiences some have. Believe me I fiddled around with this issue ALOT I think I tested 50+ sdcard's and 50 USB sticks. Ofcause there where bad apples (needed squeezing or adjustment) and one even seemed to burn out, but the majority had no corruption errors at all so ofcause I chose a few of them (only around 7 where dodgy and some same as fully working ones). I would choose another path though if I had the problem and clock down until the sdcard was stable to.

But overclocking away, speed won't matter much if you use USB 2 memory sticks no, because the rely on almost the same memory technology as sdcard's. Move to a good USB 3 stick (closer to SSD technology) or a harddrive and database operations will be insanely faster, as high or higher than the numbers we see with f2fs.

I have plenty of data to support this if it can be of any help? I work at a place where they produce these things for other labels. Hence the abundance of components.