I've also been looking into buying a microSD card for my n900. Play.com have some really cheap class 10s:

16GB Micro SD Memory Card / Class 10

8GB Micro SD Memory Card / Class 10

Seems cheap to me considering I paid about the same price for a class 4 card.

Mmm. Some good, some less good reviews. There seems some doubt as to whether these are actually PNY cards. Hope the one you plum for turns out well. If you do get one, post how it runs in our most particular of devices (N900) my only advice is check the returns T&C before you actually get one.

Has anyone tried one these UHS-I SDHC cards in the N900?

I think this thread is quite a good idea. Ensure nobody wastes their money, I guess.

I have an 8GB class 6 card that reports itself as 8.5MB/s write and 14MB/s read speed. Always worked perfectly in the N900 and my Vega.

I'll get a link to the card when I find it.

EDIT:

http://www.amazon.co.uk/Transcend-mi.../dp/B001IAMME8

nice, hopefully i made a good half blind pick from amazon.com then. reading the class 10 card reviews, i just couldnt pull the trigger with like 18 people writing that their card died after just 2+ days of usage.
EDIT:

I see two problems with this list:

first, except for a few known makers (Sandisk, Transcend, Toshiba), the brand which is printed on the card says nothing about what card it is. "Cardsforcheap" (fictional name) just prints the "Cardsforcheap" brand on whatever low priced excess inventory they got that particular week. Next week, you'll get a completely different card under the exact same reference.

second, one of the big problems with microSD are the contacts. You'd be surprised how many malfunctioning cards can be resurrected with a Q-tips and alcohol or contact spray. The cards are not designed to be taken in and out regularly, but to be put in a phone and left there (so that you can choose how much memory you need). The contacts in your N900 can also be cleaned by inserting a card slightly wet with contact spray in and out a few times.

I have an 8gb Class 6 Transcend card and it works pretty well... But I cant lie to you, I didn't stress it or test it a lot.
I have Nitdroid/Easy Debian in MicroSD
Easy Debian is smooth as f*ck
Nitdroid is somehow slow

I'll do some benchmarks and I'll tell you then

Going to do this the fast way and concat the replies...

Yes. I was trying to be a little more public-spirited than just asking "what's the best card?". The wiki is designed to be a lot more permanent than any given thread, which is why I thought it'd be good to gather the results there.

Ouch. Exactly what I'd like to avoid, especially with our picky device!

Re: (1): I agree with your point about brands and the tables. The tables are simple, possibly simplistic, but the idea is to gather users' experiences with cards, primarily for the well known brands, while requiring users to make the least amount of effort to post information. Perhaps there should be a comment to say that knock-off unbranded cards offer knock-off performance and reliability? I thought that was implied with the "all cards are not equal" phrase? Importantly, some people, such as vi_, have experienced unfortunate results, even with a card from a well known brand; it's these that are very important.

Re: (2): This is very useful information. When you have a min, would you stick something in the wiki about these maintenance and longevity tips. Otherwise, I can do it when I do the round up.

The three areas I can think of that one has a need for speed are recording video (directly to the card), I/O of large files and running an OS directly from the card. You clearly do 3, probably 2 and possibly 1 so if you fancy B/M-ing, great, but by the looks of it, your general usage is equal to, or greater than, the needs of most users so there's no need.

Thanks to everyone so far, keep 'em coming...

there is no way to get some unique manufacturer level info off the card?

Is the maintenance section accurate - please do edit if you like.

@icravovicz:
Do you mean like getting the info for a hard-drive with a pc? Trouble is, they're so cheap to make and so ubiquitous all the info they're likely to contain is a serial nmber (if that), which'll mean very little. My thoughts, anyway.

Sometimes I think that quality reports are less about the hardware than about the user. So I take them with a grain of salt. I personally have good feelings about Patriot, and some bad reports won't change my mind. I doubt you are going to collect thousands of reports, so I don't think this thread will be particularly reliable in a statistical sense.