Late to the discussion, but I thought I mention my experiences of resent:
Sew and So - they are great and the shipping is super fast - great selection as well
Patchwork Rabbit - great selection of charts especially if you like the primitive styles and best price for GAS threads I found. Great fabric and thread selection as well and super fast delivery for almost no charge. I ordered from them yesterday and they ran out of one of the threads - I got an email straight away with an apology and offer of either waiting and it being posted later or refund. I found them very accommodating all the time.
Polstitches - Jo is great in coming back with postage prices as they might be a little intimidating on the website. Great fabric as well. Love my opalescent linen for Gigi from Mirabillia.
Jodyri Designs - I asked Michelle's advise on the fabric colour for her RED kit and she was more than helpful and even sent me a picture of the fabric once it was ready to ship with the threads from the kit so I can see the finished colour effect. The fabric took a little while, but it is hand dyed to order, so no complaints there. Customer service was great and I love the linen.
These are just 4 out of the few I used up to now, but I will definitely come back to them again. In fact, I will need to stop for a little while and concentrate on my WIPs and future plans.