My personal experience with dvdrentals.ie / screenclick.com was poor - when I moved house and rejoined, they continued sending DVDs to the old address as well as the new address and billed my credit card on the double. When I spotted this and emailed them, I got an angry reply saying basically "it's your own fault". But they did eventually agree to refund.
However, despite this, they continued to bill on the double, for another couple of months!
I eventually got a refund of the double billings, but it took several emails and a bit of time on my part to obtain it. No apology either.
This, combined with high price, and the slow delivery of DVDs via An Post, made the experience fairly negative, and I cancelled the subscription.
There's definately a gap in the market for a reasonably priced DVD postal service in Ireland similar to what NetFlix.com provides in the US, especially if they can source the kind of arthouse/foreign language movies that normal high-street DVD rental stores don't stock.
However, the screenclick.com had in my experience high prices, slow delivery, a mainstream selection and bad customer service.
This was about six months' ago - perhaps they've improved.
-- James