Well, I said I'd post back with my thoughts on this phone - the Android S3 i9377 - so here I am.
I've had it about ten days now and it's pretty awful.
Overall build quality is acceptable for the price but when you hold a Samsung S3 in your hand there's a big difference. The screen is decent indoors but is difficult to read even in overcast light and almost invisisble in sunshine, even on max brightness. It's reasonably responsive, viewing angles are decent.
More importantly, I rarely get a signal. I'm on Orange using an iphone 4 and I thought that had weak reception, this Android is abysmal. I almost never get a signal inside any building, at home, at work or in a shop. Today the phone is saying "mobile network not available" all the time. Looking in the SIM Management options everything looks good but even when I've got a signal bar showing it won't connect to either voice or data services. Last week, when I did get a signal out and about, it was trying to switch on roaming, which presumabaly would have cost me a fortune. I tried GPs and it was all over the place, even after I'd allowed it plenty of time to find its bearings. This ran the freshly-charged battery down very quickly. It reported 15% power and then the phone died a couple of minutes later.
In short, don't touch it, it's a piece of ***.
Errm, anyone want to buy an Android phone?